Factors affecting our health with age
Ageing is a normal complex phenomenon and is to be distinguished from ill health. Among the many definitions of ageing from a biological point of view, one can find “Changes in our body that, over time, reduce our capacity to repair and adapt to our environment, decrease our physiological capacity for self-regulation and our probability of survival.”
For example, intercellular communication decreases, stem cells are depleted and within our cells our DNA is less stable. Our mitochondria (producing energy, reducing oxidative stress and managing the survival of our cells) malfunction.1 This leads to a slowing down of the functions of our organs: it is common, for example, for vision or hearing to diminish a little, or for our immune system to be less responsive.2 Ageing is affected by internal factors (genetics, metabolism, hormones…) and external factors (environment, lifestyle, infection, stress…), which can sometimes be modified, the sooner the better.1
Our lifestyle determines our level of exposure to factors leading to oxidative stress and inflammation. In the long term, this excess oxidative stress affects the functioning of our organs and can lead to disease. As we age, we accumulate small dysregulations in our bodies and when the body no longer has enough resources to counteract them, they can cause damage and harm to our health. But no disease is inevitable with age, so getting older is not enough to cause chronic disease.1
The role of oxidative stress
As mentioned in the previous paragraph, the accumulation of oxidative stress seems to be involved in many of the health problems that occur with age. It is due to a production of free radicals and oxygen and nitrogen ions (reactive oxygen and nitrogen species – RONS) that is too strong to be counterbalanced by antioxidant defences. These RONS come from our body’s normal cellular metabolism on the one hand, and from exogenous sources such as air and water pollution, tobacco, alcohol, heavy metals, certain drugs, smoked fats or foods, radiation… They cause major changes to our DNA, proteins, lipids, carbohydrates, cells and their mitochondria, which, accumulated over the long term, can cause problems in functioning. Fortunately, we have antioxidant defences: enzymes that can convert these RONS into harmless molecules, and molecules that interact with the RONS and stop the chains of reactions.3-5
Often, the presence of significant oxidative stress correlates with the presence of relatively low but constant inflammation, as their biochemical pathways of activation are interdependent.6 This chronic inflammation also damages our organs. Learn more about oxidative stress and inflammation.
We can support our antioxidant defences through our lifestyle: by minimising exposure to exogenous RONS, which are unfortunately very present; by regular and moderate physical activity, as studies have shown that both inactivity and high-intensity sport increase oxidative stress, while regular endurance increases antioxidant defences; by taking care of our diet and consuming antioxidants.3
Ingredients to limit oxidative stress
Green tea, for example, with its polyphenols (e.g. epigallocatechin gallate), increases the amount of antioxidants in the plasma and the activity of antioxidant enzymes. Fewer DNA mutations were observed in animals, an anti-inflammatory effect was present, and green tea may also have some anti-cancer effects.7,8 It may also be useful for metabolic syndrome, type II diabetes, obesity, and cardiovascular or liver disease, particularly by acting on carbohydrate and lipid metabolism. However, beware of over-consumption of tea, especially for people with iron absorption problems.9,10
Rosehip is also a powerful ally against oxidative stress, due to a high concentration of flavonoids, vitamin C and specific galactolipids. By increasing the activity of antioxidant enzymes (such as superoxide dismutases SOD, catalases…), rosehip helps to reduce the concentrations of free radicals and nitrogen oxides (RONS) that can damage tissues. It also ensures good communication and adhesion between cells, is a powerful anti-inflammatory and can reduce pain. It can be useful for osteoarthritis, rheumatoid arthritis, osteoporosis, diabetes, as well as protecting the skin and improving the digestive and immune systems.11
Pomegranate is also an antioxidant, thanks in part to its polyphenol ellagic acid, which helps eliminate toxins, protects against free radicals by activating antioxidant enzymes, and limits the production of pro-inflammatory cytokines. It is particularly useful for skin health (UV toxicity) and may have antitumour effects.12
Edelweiss and yellow gentian are two anti-inflammatory, antioxidant and analgesic alpine plants. They can be used for joint or cardiovascular problems, gastrointestinal health and skin integrity.13,14
The properties of melon should not be overlooked either. Melon is high in SOD, an essential antioxidant enzyme. Several studies have highlighted the antioxidant and anti-inflammatory properties of melon, which reduces the production of inflammatory cytokines and free radicals.15 It is also useful for limiting mental and muscular fatigue and stress.16
Coenzyme Q10 is a cofactor found in mitochondria (the part of the cell that produces energy, reduces oxidative stress and prevents cell death). It is therefore a powerful antioxidant and cell protector. Taking coenzyme Q10 orally increases the concentrations of Q10 throughout our body, for example in our brain and eyes. Cardiovascular diseases and chronic inflammation can also be relieved by the antioxidant power of Q10.17
The impact of the menopause
The menopause is the complete cessation (more than 12 months) of menstruation, due to the decrease with age in the number of ovarian follicles and therefore in the level of oestrogen, which interrupts the hormonal cycle causing the menstrual cycles. The woman can no longer have children. The median age of menopause is around 51 years.
It is a normal phenomenon and not a pathology, even if certain unpleasant symptoms are recurrent: hot flushes and night sweats, migraines, vaginal dryness and urinary problems, weight gain… as well as other longer-term effects such as osteoporosis or cardiovascular risks (oestrogens promote the flexibility of blood vessels). Almost half of the women also experience psychological symptoms such as irritability, anxiety, depression, loss of self-confidence, lack of concentration or sleep problems. But not everything is negative, as this phase of life can also be welcomed as a liberation. The end of menstruation can therefore be experienced positively and with serenity.
Meditation and breathing exercises can help with this, as can attending information sessions to understand what is happening. Regular sport has a positive effect on the cardiovascular system, bones, muscles and weight, as well as on mental well-being. In contrast, alcohol and emotional stress can worsen symptoms.18-20 There are some treatments to limit symptoms, often oestrogen substitutes or oestrogen receptor modulators, but with some side risks. Many nutrients can be effective in preventing some of the health effects of menopause, such as phytoestrogens (from soy or flaxseed) or calcium and vitamin D for bones.20
Skin ageing
The skin is a barrier between our body and the outside world, protecting us from aggressors, retaining water and controlling our temperature. The skin has three layers: the epidermis, the dermis and the subcutaneous tissue.
As the skin ages, these three components undergo changes. Some changes are obvious: wrinkles appear and elasticity decreases. Indeed, our skin cells are no longer as efficient, the fibres (collagen and elastin) that give structure and elasticity to our skin are less numerous, melanomas fill up with melanin creating dark spots… The causes are numerous: Internal, such as genetics, cell metabolism and hormonal changes (e.g. at menopause), but also external, including sun exposure (UV), pollution, chemicals, oxidative stress, regular sugar consumption, smoking, skin care, sleep, stress… UV for example promotes the destruction of extracellular matrix fibres (collagen, hyaluronic acid) and damages mitochondria (part of the cell responsible for reducing oxidative stress, cell survival and energy production). 21,22,23
As the famous quote goes “You never get a second chance to make a first impression”, so every second is important in the quest for healthy aging in general and skin aging in particular.
- Ingredients for the skin
Collagen is the most abundant protein in the human body and in mammals. It forms fibres in the extracellular matrix, giving shape and mechanical properties to tissues. There are 28 types of collagen in our body, of which the first 3 are the most abundant. Types I and III are the ones most commonly found in the skin as well as in bones and nails. Collagen improves the health of the skin and has anti-ageing properties, reducing wrinkles, thickening of the epidermis, redness and water evaporation. It increases skin hydration and elasticity and reduces the impact of UVB on skin dehydration.24-27 It has also been shown to be effective in wound healing, particularly post-surgical,28 and in the healing of pressure sores (pressure ulcers on the skin due to soft tissue compression between a hard surface and bone, mainly in bedridden people).29 Collagen peptides reduce the severity of rashes in atopic dermatitis, as well as transepidermal water loss and inflammatory biomarkers in skin keratinocytes.30 People with cellulite also benefit from the virtues of collagen hydrolysates. Taking them for 6 months has shown a reduction in cellulite, skin rippling, as well as an increase in dermal density and improved appearance.31
Lysine is one of the amino acids necessary for collagen synthesis and then for its optimal function. It plays a key role in collagen structure, as it allows the links within and between collagen chains.32 Lysine also inhibits MPPs, the enzymes responsible for collagen degradation.33 These properties make lysine an ideal ally in supporting wound healing. In the skin, it facilitates cell proliferation, modulates inflammation and angiogenesis (vascularisation) and may even have an antimicrobial action, especially against herpes, which accelerates healing.34,35
Valine is one of the branched side chain amino acids (BCAAs) along with leucine and isoleucine. They are important in the synthesis of collagen, especially types I and III in the skin.36 In combination with other amino acids, BCAAs may restore collagen synthesis in the dermis, which is compromised by UV radiation.37
Glucosamine is a monosaccharide naturally present in our body and is the precursor of several very important constituents of the extracellular matrix (hyaluronic acid, chondroitin, keratan…). Widely used for its benefits for the joints, glucosamine, through the molecules of which it is the precursor, also helps to improve skin hydration and reduce wrinkles. In addition, it can regulate melanin production, be useful in treating hyperpigmentation and be beneficial in accelerating healing, especially in the case of burns.38-40
Hyaluronic acid protects against oxidative stress, by reducing free radicals and increasing antioxidant synthesis. It also mitigates inflammation by reducing the production of pro-inflammatory mediators, such as cytokines, bradykinin and prostaglandin, thereby limiting over-inflammation.41 As wound healing involves a complex sequence of remodelling of the extracellular matrix, hyaluronic acid regulates the coordination of the various steps involved. By influencing the tissue microenvironment and binding to cell receptors, it can influence cell behaviour and function, as well as gene expression, for example in skin and mucous membranes.41-44 Due to its viscoelastic and water-retaining properties, hyaluronic acid is a very good moisturiser for all tissues. Taking hyaluronic acid has a clear benefit for the health of the skin. Indeed, taking it for 6 weeks allows an 8% increase in skin hydration, still visible 2 weeks after the end of the treatment.45
Ellagic acid is a polyphenol found in certain fruits and vegetables, mainly berries, pomegranates and certain oilseeds. It is known for its antioxidant properties: it helps eliminate toxins and protects against free radicals. Ellagic acid is a good photoprotector for the skin: it helps limit the production of pro-inflammatory cytokines and free radicals (oxidative stress), as well as the degradation of collagen due to UV-B, which reduces wrinkling, thickening of the epidermis and pigmentation, making the skin brighter.12,46-48 Some studies on mice even suggest that it could be a good treatment for inflammatory skin diseases (dermatitis, oedema), or for wound healing.49,50
Coenzyme Q10 is a cofactor found in the mitochondria (the part of the cell that produces ATP energy) and a strong antioxidant. It is very useful in protecting the skin from UV rays which can cause oxidative stress damaging DNA, lipids and proteins in cells, and it protects mitochondria from degeneration and allows ATP regeneration.51 It also increases collagen and elastin production and inhibits the PPMs that destroy them.52 A clinical study highlighted the reduction in wrinkles and improvement in skin smoothness after 12 weeks of taking Q10.53
Zinc is used for a multitude of processes in our body, and is involved in the formation, repair and maintenance of the skin. The skin contains about 6% of our body’s zinc, and as we cannot store it, a regular supply is important. The skin is constantly renewing itself and many enzymes need zinc to function. For example, it is useful for stabilising cell membranes, managing oxidative stress and blocking UV light. It helps to improve wound healing because many of the enzymes involved in this process need zinc to function.52,54 Zinc can also be used in the treatment of inflammation, acne, dermatoses and pigmentation problems.55,56 Zinc is approved by EFSA* to help maintain normal skin and protect cells from oxidative stress.
Copper is involved in the synthesis and stabilisation of extracellular matrix fibres. It therefore helps to improve skin elasticity and healing and reduce wrinkles. It is also useful for its good vascularisation. It also has antiseptic properties against certain viruses, bacteria and fungi. These benefits explain why it has been used for thousands of years for the treatment and maintenance of the skin.57 Copper contributes to the maintenance of connective tissues, of which the skin is a part, to the protection of cells against oxidative stress and to the normal pigmentation of the skin, according to EFSA*.
Manganese is an essential metal for certain antioxidant enzymes, particularly in the skin. Thus, manganese intake helps to protect skin cells against the effects of oxidative stress and UV light.58 As oxidative stress increases the signs of ageing, manganese also limits the formation of wrinkles, maintains skin firmness and improves healing.59 EFSA* points out that manganese contributes to the maintenance of connective tissues, of which the skin is a part, and to protecting cells against oxidative stress.
A combination of zinc, manganese and copper appears to be particularly effective for skin healing, as they act on different cells and phases.60,61
Selenium is involved in several processes involved in reducing oxidative stress and its damage. It can prevent the damaging effect of UVB which can kill skin cells. It is present in selenoproteins, which are involved in the proper functioning of skin cells, among other things, and is useful in wound repair.52 Selenium protects cells from oxidative stress*.
Hair and nails
Our hair and nails also age. Their growth, structure and colour change. In the hair, the fibres in the roots are weaker, the melanocytes responsible for the colour function less well, and the cells in the follicle decrease in hair production. The nails are more fragile, thin and discoloured, the morphology of the nail plate (which grows the nail) changes and their lipid content varies with age. This is normal because the cells degenerate progressively, but oxidative stress and the environment (care, pollution, sun …) have also had time to impact. It is important to take care of them, from an aesthetic point of view, but also to avoid some of their problems which can impact on the quality of life.62-66
- Ingredients for hair and nails
Millet is a grain that contains many amino acids, B vitamins, silicic acid and minerals, including manganese. Millet extract combined with amino acids and calcium is believed to improve hair growth (anagen phase).67
Biotin is one of the B vitamins, useful for many functions of our body. For the nails, taking biotin makes them firmer and harder, and is effective in limiting brittle nails.68,69 Moreover, according to EFSA*, biotin contributes to the maintenance of normal skin and hair.
Collagen helps to promote nail growth, reduce nail breakage and generally improve the appearance of nails.70,71 Hair also benefits, as collagen intake increases cell proliferation and hair thickness.72
Selenium contributes to the maintenance of normal hair and nails, according to EFSA* For example, selenium deficiency appears to be involved in hair loss and non-colouring,73 with the recommended daily amount being 55µg.
Immune system
Our immune system is essential for our survival and is extremely complex. Many micro-organisms live in harmony with us and are very useful, but some can damage our tissues, these are the pathogens. Our first barrier is physical (skin, mucus, healthy bacterial flora…) and prevents some pathogens from infecting us. Then, if a pathogen gets in, our innate immunity cells act immediately, but in a way that is not specific to that pathogen. Some of these cells will also secrete molecules (cytokines) to attract more innate immune cells. This leads to the symptoms of inflammation (redness, pain, swelling, heat – e.g. fever -), caused by the increased blood flow and infiltration of immune cells into the attacked tissue. Inflammation is a good thing here because it helps to fight the pathogen and activate the innate immune system (it is chronic inflammation, often due to our lifestyle or chronic diseases, that is a problem, as our body is constantly fighting). Some of these innate cells will also go to the nearest lymph node and inform the rest of the immune system of the type of pathogen infecting us, and select cells that will be more effective in fighting it. This is adaptive immunity, which is very effective and precise, but takes around a week to become active. Finally, when the infection has been overcome, everything returns to normal, but the body keeps a memory of this infection thanks to memory lymphocytes. So, if the same pathogen re-infects us, our body can react more effectively and quickly.
Thanks to the memory lymphocytes, we are protected from more and more diseases as we age because we recognise and fight them immediately. But the functioning of our immune system cells slows down with age and we are more vulnerable to unknown diseases or pathogens that mutate very quickly (e.g. the flu virus, which is different every year). It is therefore important to take good care of your immune system, including a healthy lifestyle.
- Ingredients to support the immune system
It is well known that vitamin C helps to maintain the normal functioning of the immune system, to protect cells against oxidative stress and to reduce fatigue, claims authorised by the EFSA*. Indeed, numerous studies have highlighted that vitamin C promotes T-cell maturation (adaptive immunity) and improves immune system function.74 It is also a key antioxidant for detoxifying free radicals (ROS).75
Vitamin D is an essential element that contributes to the normal functioning of the immune system, according to EFSA*. It can bind to receptors on immune cells and thus modulate innate and adaptive responses.76,77 Vitamin D also enables cells to better resist stress.78 One study found that children taking vitamin D3 had a reduced incidence of influenza.79 In contrast, vitamin D deficiency has been associated with an increase in autoimmune disease and susceptibility to infection.
The 8 B vitamins influence many cellular processes and their deficiency has been linked to a number of dysfunctions, including immune, inflammatory and nervous systems.80,81 Taking vitamin B6, for example, improves immune function82 and B5 can limit bacterial growth by stimulating the immune system.83 Biotin is essential for the proper functioning of our cells. It is a cofactor for many enzymes central to the metabolism of cells, including lymphocytes (immune cells). When it is lacking, the immune system does not function properly and inappropriate inflammation develops.84-86
Vitamin E supplementation has clear benefits for the stimulation of the immune system, for example on the proper maturation of T cells (adaptive immunity). These effects are particularly important in older people with weakened immune defences. It also reduces susceptibility to infections, limits the effects of oxidative and immune stress on cells and facilitates the elimination of certain pathogens.87-91
A β-glucan is a polysaccharide found in oats, among other things. It increases the immune system by activating parts of the immune system (complement system) and stimulating the production of cytokines.92,93 Studies have shown that taking β-glucans reduces the risk and duration of respiratory infections in adults, the elderly and children under 4 years of age, while improving vigour, mood and reducing tension and fatigue.94-96
Choline is essential for the synthesis of phospholipids (components of cell membranes) and for the maintenance of homeostasis of inflammation molecules. It also regulates the activation of the immune system. Thus, it can help fight pathogens and also plays a role in reducing oxidative stress. 97-99
Zinc is a molecule recognised by EFSA* for its effects in contributing to the normal functioning of the immune system and protecting cells against oxidative stress, among many other functions. For example, zinc is necessary for neutrophils (immune cells) to form their ‘net’ and eliminate pathogens. It plays an important role in modulating the pro-inflammatory response, regulating inflammatory cytokines and controlling oxidative stress. Thus it is useful against viral (colds, diarrhoea, HIV…), bacterial and parasitic infections.100-103
Calcium appears to play a central role in the activation of immune cells. It acts as a messenger between cells, particularly lymphocytes, regulating the different stages of their development and maturation.104,105
Magnesium also has a strong relationship with the immune response, both innate and adaptive. It is required for the synthesis of adhesion molecules, receptors and antibodies. It is also required for lymphocyte proliferation, proper functioning and certain immune responses. Magnesium deficiency can lead to inflammation, cell death and impaired immune cell function.106-108
Selenium plays a crucial role in the development of many physiological processes, including the immune response. However, approximately 50% of the Swiss population is deficient in selenium (less than 100 µg/day), which can cause numerous problems (metabolic, nervous, immune, allergic, etc.). However, be careful, more than 850 µg/day can lead to intoxication. Selenium intake stimulates the immune system (activation of cell proliferation and functions) and can modulate inflammation of the respiratory tract thanks to its antioxidant capacities. Numerous studies on rodents have shown that an optimal amount of selenium can eliminate many pathogens more easily, giving it an “antiviral” effect.109-111
Rosehip’s comprehensive composition makes it a very good ally against winter ailments, such as colds and flu, by boosting the immune system, especially due to its high vitamin C content.112 Its phenolic compounds also correlate with antimicrobial properties. Although the mechanisms are not fully defined, it appears that it can decrease the energy of pathogens and suppress some of their enzymes that act as virulence or resistance factors. It also modulates inflammation: enough for the immune system to be effective, but not so much that it destroys tissue.11
In addition, glucosamine supplementation has been associated with a significant reduction in all-cause mortality (cancer, cardiovascular, respiratory, digestive, etc.),113-115 in particular due to its anti-inflammatory properties, which are useful for many ailments.116 It has been used, for example, to alleviate inflammatory bowel disease (IBD), migraines or viral infections.38
Bones and joints
Our musculoskeletal system allows us to be stable and mobile, which is useful in every moment of our daily lives. Chronic joint pain is unfortunately very common with age, to the point where it seems almost normal to have it. The causes can be varied, but osteoarthritis is one of the major joint disorders. Injury, sedentary lifestyle, overweight, repetitive movements, oxidative stress, as well as inflammatory, genetic and metabolic factors, can all contribute to the degeneration of joint cartilage.18 Physical rehabilitation is particularly recommended to maintain the mobility of the affected joint, as is an assessment of one’s lifestyle (good sleep, sugar-free and plant-rich diet, weight loss, etc.).
Osteoporosis is another widespread skeletal disease (1 in 3 women and 1 in 5 men over the age of 50): the bone becomes demineralized because calcium and phosphorus can no longer be fixed and bone resorption becomes faster than its renewal, making the bone fragile and predisposing to fractures and reducing quality of life. Alcohol, smoking, use of corticosteroids, lack of vitamin D, previous injuries, low BMI, certain genetic factors, metabolic disease and the menopause can increase the risk of osteoporotic bones. There are medications available, including bisphosphonates, but they can have serious side effects. Regular moderate physical activity to strengthen muscles, as well as calcium and vitamin D3 (necessary for calcium absorption and transport), are recommended. Similarly, a good protein intake, combined with an adequate calcium intake, would limit the risk of fractures.117 Finally, the role of a high intake of fruits (fresh and dried) and vegetables is essential for adequate bone remodelling and reduction of inflammation and oxidative stress. They are rich in minerals (potassium, phosphorus, manganese, boron, copper…) and vitamins (B, C and K): potassium, for example, would help balance the acidity of our body and the conservation of calcium in our bones.118
- Ingredients to support bones and joints
Calcium is the best known mineral for bone health and maintaining good bone mineralization.119 However, experts stress the importance of combining it with vitamin D to increase bone mineral density, limit osteoporosis and some fractures, although the results are more mixed in the latter case.120,121 Vitamin D regulates intestinal calcium absorption.122 Good calcium intake also appears to be correlated with a reduced risk of osteoarthritis of the knee,123 which may be explained by inhibition of cartilage cell (chondrocyte) death by blocking inflammatory cell pathways.124
Supplementation with vitamin D (which is poorly synthesised naturally by our bodies in winter and when we spend a lot of time indoors) has been shown to be associated with a significant slowing down of abnormalities in the knee (joint structure and cartilage composition).125 Inflammation and oxidative damage can also be reduced, improving protein and DNA function.126,127 In addition, vitamin D supplementation may limit musculoskeletal pain and prevent osteoporosis in these patients.128 Finally, vitamin D is an important mediator and is involved in the regulation of immune responses and inflammation, a key role in autoimmune diseases such as arthritis.129
Zinc is a potent antioxidant and is involved in the proliferation of chondrocytes (cartilage cells). Thus, zinc supplementation may prevent the progression of osteoarthritis.130 Zinc also appears to play an important role in preventing or even curing osteoporosis, as it stimulates bone mineralisation and bone formation by osteoblasts and inhibits bone resorption by osteoclasts.119,131 The recommended daily dose of zinc is 10mg/d, as too much consumption may lead to nausea or headaches.
Vitamin K is involved in the mineralisation of bone and cartilage, as well as in the regulation of articular cartilage matrix genes and certain enzymatic reactions.132 People who are deficient in vitamin K are at increased risk of damage to cartilage and subchondral bone, and thus of developing osteoarthritis and other joint diseases,132-135 whereas an adequate daily intake would appear to be protective.136 Vitamin K is also essential for bone health, affecting bone strength and metabolism, particularly by promoting the activation of bone-forming cells (osteoblasts) and extracellular bone matrix mineralising proteins.137 In addition to its role in mineralisation, vitamin K appears to have an anti-inflammatory action, which is useful for many chronic diseases (cardiovascular, osteoarthritis, osteoporosis…).138,139
The benefits of collagens I and III are important for bone health, and are particularly useful in cases of osteoporosis, especially postmenopausal, by decreasing the presence of markers of bone breakdown and increasing mineral density and markers of bone regeneration.140-142
Glucosamine is a monosaccharide naturally present in our body and is the precursor of several very important constituents of the extracellular matrix (hyaluronic acid, chondroitin, keratan…). Its benefits for the joints are well established. In cases of osteoarthritis, often combined with chondroitin, it can reduce pain and increase mobility, by reducing cartilage degradation, restoring the extracellular matrix, and limiting inflammation and oxidative stress.143-145
Musculature
Muscles allow us to perform precise movements, maintain our balance and posture, and generate heat. Our muscle mass decreases with age and our strength decreases in parallel (by 10-15% per decade up to the age of 70, 25-40% after), which can lead to sarcopenia. The consequences of reduced muscle mass include a marked increase in the risk of falls and fractures, as well as poor balance and reduced ability to move.146
To care for our muscles, which are plastic and can adapt throughout our lives, regular and moderate physical training is essential. Endurance exercises coupled with muscular resistance exercises can improve the cardiovascular system and muscle strength and mass, both in young and old.147 Good nutrition is also essential, with enough protein (more than 1g/kg/d), vegetables (alkalizing power and presence of potassium), vitamins, minerals, antioxidants, unsaturated fatty acids…
- Ingredients to support the musculature
In addition to its essential role in bone mineralisation, calcium is required for proper muscle function, as it regulates muscle contraction.148 Calcium is also a regulator of muscle growth, maintenance and regeneration (e.g. after injury), particularly through its action on muscle stem cells. We therefore need calcium to promote muscle regeneration and to prevent muscle loss with age.149
Magnesium also plays a vital role, as it is used by over 300 enzymes in many of our body’s functions.150 It is involved in maintaining muscle function and contraction and in energy production. Magnesium intake can increase strength and physical and muscular performance in athletes and especially in non-athletes or older people, particularly by increasing glucose availability and reducing lactate accumulation.151,152 Magnesium intake also appears to prevent muscle damage in competitive cyclists.153
Energy, vision and the nervous system
Our nervous system consists of our nerves, our brain and our spinal cord linking the two. We process information from our 5 senses and send messages, conscious and unconscious, to our body. Coordination of movements, mobility, spatial orientation, problem solving and planning, emotions, decoding of sensory information, attention, language, memory, control of appetite or sleep, reflexes and reward mechanisms, unconscious control of blood glucose levels, hormone production, breathing and heart rhythms… are part of our daily functions. Vision is one of the senses we use the most. Our eyes and brain work together to transform light into an image, from the pupil to the retina and then to the visual cortex via the optic nerve. As we age, inflammation and oxidative stress may have had time to take hold, which can cause certain diseases and lower our visual acuity.
Over the course of our lives, our neural plasticity and information processing speed decreases, as our cells’ ability to repair and create new networks is reduced. Nevertheless, while some functions may decline with age, others remain intact and may even benefit from accumulated experience. In any case, the nervous system remains plastic and some functions can be improved with time and training. Factors such as regular exercise, good sleep, limited stress, intellectual stimulation, healthy nutrition and limited alcohol intake appear to be beneficial in maintaining a functional nervous system. In addition, certain nutrients play a protective role.
We all need energy in our daily lives. This energy is produced by each of our cells, thanks to their numerous mitochondria. The mitochondria continuously convert the air we breathe and the nutrients from our food into large amounts of energy called ATP. ATP is needed for almost every action in each of our cells and therefore for the functioning of all our organs. Moving a muscle, talking, blinking, thinking, digesting… everything uses ATP. And our brain is one of the biggest consumers: although it weighs only 2% of our body weight, it consumes about 20% of the energy we spend at rest (~ 300 kcal / day).
- Ingredients for vision, the nervous system and energy
There are 8 B vitamins (thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), vitamin B6, biotin, folate (B9) and vitamin B12). These vitamins contribute to energy production, nervous system function, maintenance of vision, psychological and cognitive functions and protection of cells against oxidative stress, according to EFSA*. They are involved in DNA repair and neurotransmitter synthesis and are thought to limit cognitive decline and visual acuity loss. In addition, multivitamin B supplementation may reduce inflammation and oxidative stress in the brain and improve energy storage and cellular metabolism.154-157
Magnesium is required for more than 300 reactions in our body, including neural transmission and muscle contraction. Deficiency (affecting more than half of the Western population – recommended ADI 300-400 mg/d) has been associated with many conditions, such as migraines, metabolic problems such as diabetes, some cardiovascular problems, cataracts, osteoporosis, asthma etc.158,159 Magnesium is important for eye health, and a deficiency has been linked to many eye problems, which can be limited by supplementation.160,161 It can also be very helpful in limiting pain,162 and in increasing cognitive performance.163 Furthermore, interacting with biochemical stress pathways, stress and hypomagnesemia amplify the negative effects of each other. Both have been associated with migraines, chronic fatigue, fibromyalgia, physical manifestations of stress, chronic pain, anxiety, depression, among others. The brain is particularly sensitive to stress, and magnesium intake could prevent some neuronal damage caused by glucocorticoids released during acute stress situations, and limit certain self-destructive behaviours during a stressful situation (smoking, overeating, alcohol, risk-taking…).164,165
Metals, such as zinc and copper, are essential for retinal health, including the proper functioning of phototransduction and neurotransmission involved in visual information processing. Zinc is, for example, required for photoreceptor membranes, light response and synaptic transmission. Zinc and copper, which often decline with age, are also crucial for the proper functioning of antioxidant enzymes, which are very present in the retina and allow the reduction of oxidative stress that can damage it.166,167 A homeostatic level is essential because both a deficiency and an excess can lead to retinal dysfunction. Zinc deficiency, for example, can be implicated in poor night vision, even age-related macular degeneration or diabetic retinopathy, and copper deficiency can be linked with optic neuropathy.168,169 On the contrary, zinc supplementation may slow the progression of age-related macular degeneration, the main cause of blindness.170 Zinc’s function in the immune system and regulation of inflammation is also important for maintaining eye health.171 According to EFSA*, zinc contributes to the maintenance of normal vision.
Copper influences energy metabolism and body composition.172 Zinc is also involved in cellular energy metabolism, mitochondria and DNA maintenance and can protect our cells.173 Copper is present at high levels in the nervous system, plays a role in cellular energy production (ATP), is present in many enzymes and modulates synaptic transmission of neurotransmitters.174 Zinc and copper deficiency has been associated with neuropathies leading to motor difficulties and pain.175 Copper’s antioxidant action is also essential for proper communication of neurons and astrocytes,176 and for proper neurological function.177 Zinc plays an essential role in brain development and maintenance of brain function throughout our lives, being key to 300 enzymes and modulating synaptic activity, neuronal plasticity and cell survival. Altered zinc levels have been implicated in brain problems (e.g. stroke, brain injury), neurodegenerative problems (e.g. Alzheimer’s) and psychological problems (e.g. depression).178-180 According to EFSA*, copper contributes to normal nervous system function and reduced fatigue, zinc contributes to normal cognitive and psychological function.
The Acceptable Daily Intake of copper is 9mg/day, and if a deficiency is harmful to our health, an excess is also problematic for our cells.181 The ADI for zinc is around 10mg/d, more than 50mg/d could have a toxic effect on our cells.182
Coenzyme Q10 is a cofactor found in the mitochondria (the energy-producing part of the cell) and a strong antioxidant. As a component involved in the chain of reactions to convert carbohydrates and fatty acids into usable ATP energy, Q10 is an essential nutrient for every cell and organ function. 183,184 For example, taking Q10 can restore proper muscle and brain function,185 whereas a deficiency can lead to a variety of problems.186 As well as increasing our energy, it also boosts our immune system.183,187 It is also a powerful neuroprotectant, for example by preventing apoptosis (cell death) and scavenging free radicals.17 It can also reduce eye damage, for example from UV or radiation and oxidative stress.188
L-serine is an amino acid that is useful for nucleotide (DNA) synthesis, cell division and cellular energy production.189,190 It is a conditional amino acid, i.e. it can be synthesised, but not always in sufficient quantities to meet our needs. Dysregulation of serine levels in the eyes can lead to various retinal pathologies.191 Serine is also crucial for our nervous system and brain function190 : it is neuroprotective and may be beneficial for some neuropathies.192
Metabolism
Metabolism is the set of chemical reactions that take place in our body. Many reactions need enzymes (proteins that allow the reaction to take place) and/or energy (ATP) to occur. For example, there is digestion, the transport of molecules, and many reactions within our cells: for the synthesis of cellular components (proteins, DNA, lipids, glycogen…) and for the degradation of constituents – especially food – to produce energy. It is therefore a kind of cycle: the lipids, proteins and carbohydrates in our diet are reduced to small components by our digestion and in our cells, and these small components allow the construction of new large cellular components and the production of energy in the form of ATP necessary for many reactions.
The digestion of carbohydrates is an important source of energy. Complex sugars are broken down into smaller molecules and then into glucose. This glucose passes through the bloodstream to all our cells. Insulin, produced by the pancreas, is secreted when glucose is detected in the blood (blood sugar) and helps to activate receptors on our cells so that the glucose can enter. Once the glucose has entered, our cells use it to produce ATP. If there is too much, it is stored as glycogen.
Under certain conditions (consumption of too many sugars, sedentary lifestyle, overweight, etc.) and over time, the secretion of insulin by the pancreas can be disrupted (insulin resistance) and the blood sugar level (glycaemia) will be less well regulated and will increase. This chronic dysregulation can lead to metabolic syndrome and type II diabetes, and their common cardiovascular complications.
Fats are an even more concentrated source of energy for our body. They are converted by our digestion into simple fatty acids, and then become ATP energy in our cells. However, lipids are only used once all the energy from carbohydrates (glucose) has been used. In the presence of a lot of carbohydrates, fatty acids are stored as triglycerides in the adipose tissue and the liver, and when supplies run low, fatty acids are used as a source of energy, especially by the muscles and the heart.
Cholesterol is a fat particle circulating in the blood, carried by one of three types of lipoproteins. The VLDL and LDL (-very- low density lipoprotein) types can deposit cholesterol on the walls of the blood vessels, and hypercholesterolaemia can eventually clog the vessels, causing cardiovascular problems. The HDL (high density lipoprotein) type, on the other hand, captures the cholesterol circulating in the blood and brings it back to the liver to be eliminated.
- Ingredients for metabolism
Numerous studies on β-glucans, a fibre derived from oats, have highlighted their ability to lower cholesterol, particularly LDL, but not ‘good’ HDL.193 This is because β-glucans can interact with lipids and bile acids (cholesterol derivatives that help digest dietary fats) in the intestines, thereby lowering cholesterol levels.194 EFSA* endorses their use to maintain normal cholesterol levels.
Chromium may be beneficial for the regulation of insulin, blood sugar and cholesterol, and thus reduces the risk of cardiovascular disease. Chromium is often deficient in people with type II diabetes, and chromium intake is useful in limiting glucose intolerance.195-197 The EFSA* validates its use to help maintain normal blood sugar levels.
Choline is an important nutrient and plays an essential role in lipid metabolism. It helps to reduce the amount of triglycerides and fatty acids in the blood by acting on the expression of certain genes, the activation of certain molecules, inflammation and oxidative stress. A diet too rich in saturated fatty acids can lead to liver problems (such as non-alcoholic steatohepatitis – NASH), and choline intake could help protect the liver. Choline also supports healthy muscle function.198-201 According to EFSA*, choline contributes to fat metabolism and normal liver function.
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The information published on www.swiss-alp-nutrition.ch does not claim to be complete and is not a substitute for individual medical advice or treatment. It cannot be used as an independent diagnosis, nor can it be used to select, apply, modify or discontinue treatment of any disease. In case of health problems, it is recommended to consult a doctor. Access to www.swiss-alp-nutrition.ch and its contents is at the user’s own risk.
Indications :
Food supplements should not be used as a substitute for a varied diet. The recommended daily allowance should not be exceeded. In general, food supplements are not suitable for pregnant and nursing women, children and adolescents. Keep out of reach of children.
* EFSA: official health claims of the European Food Safety Authority. An EFSA health claim is a statement about a relationship between a food and health. The European Commission allows different health claims provided they are based on sound scientific evidence.
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