expert opinion
Perspectives in nutrition and brain aging
Epidemiological studies and basic research suggest a protective effect of long-chain omega-3 polyunsaturated fatty acids, antioxidants and B vitamins against brain aging.
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Topic of the Month
Key nutrients in the prevention of eye diseases
Optimizing vision throughout the lifespan is a public health priority worldwide, not only because of its central importance to quality of life, but also because of the health care costs associated with the loss of vision in an aging population. Oxidative stress is thought to be a key pathogenic mechanism of compromised vision, and the antioxidant properties of some nutrients show the capacity to modulate disease conditions linked to oxidative stress. Considerable evidence has accumulated showing that vitamins A, C, E, beta-carotene and zinc help support vision and may be protective against the development or progression of some common – especially age-related – eye diseases such as age-related macular degeneration and cataracts. In addition, increased intakes of the carotenoids lutein and zeaxanthin and the omega-3 fatty acid docosahexaenoic acid (DHA) – all concentrated in the eye – have been associated consistently with lower likelihood of sight-threatening conditions. There has also been some promising research with B vitamins in age-related eye diseases and with vitamin A and DHA in the rare disease retinitis pigmentosa (see also Key nutrients for healthy vision).
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expert opinion
Controversies in omega-3 fatty acid research
Long chain omega-3 fatty acids play important roles in growth, development, optimal functioning, and maintenance of health and well-being right across the life course.
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expert opinion
The controversy around antioxidants and prooxidants
Antioxidant research has progressed over the past decades from the initial enormous potential of antioxidants envisioned by researchers when the free radical theory of aging was proposed, through to the current reality of positive, negative, and inconsistent results from clinical trials investigating antioxidant interventions in numerous health conditions.
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Topic of the Month
Key nutrients for healthy vision
The eye is rich in nutrients and other dietary components that support and complement each other. Some nutrients are necessary for the basic physical structure of the eye, some for the physiology of sight, and others for protection. Nutrients within the visual system can be thought of as a hierarchy representing a complex of interacting factors: while vitamin A (retinol) is essential for the formation of visual pigments, the antioxidants vitamin E, vitamin C, lutein and zeaxanthin help to protect the lens and retina against light-induced oxidative damage, and the long-chain omega-3 fatty acid docosahexaenoic acid (DHA) enriches neural tissues including the photoreceptor cells. These nutrients are known to be important for visual development early in life, starting from the fetus through infancy to early childhood. Visual acuity gradually improves until about age four, when it is comparable to that of adults. For adults a sufficient intake of these nutrients is needed throughout the lifespan to maintain visual performance, such as the ability to adapt to low light, recover from intense light and distinguish objects from their background.
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expert opinion
The role of antioxidants in menopause
Menopause, a form of reproductive aging, is defined as the permanent cessation of ovarian follicular activity and eventually, the menstrual cycle.
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expert opinion
The Importance of micronutrients for cancer patients
Depending on the location of the tumor and the sex of the patient, up to 90% of cancer sufferers take dietary supplements containing antioxidant and immune-stabilizing micronutrients.
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Topic of the Month
The safety of micronutrients – Part 3: minerals
As concentrated sources of micronutrients designed to supplement the normal diet, dietary supplements can be used to balance specific dietary deficits or to ensure adequate intakes. However, in some cases too high an intake of micronutrients can have adverse effects on health or cause undesirable side effects; for this reason it is necessary to define maximum intakes to guarantee the safety of their use in dietary supplements. Since the European legislative authority has not yet established uniform maximum intakes across the whole of Europe, manufacturers of dietary supplements and fortified foods are guided by recommended daily amounts and scientifically recognized upper limits for safe total daily intakes. This also applies to safe intakes for minerals present in the body, whether as macro-elements in concentrations of at least 50 mg per kg dry body weight, or as trace elements (micro-elements) in concentrations of under 50 mg per kg body weight (see also The safety of micronutrients – Part 1: fat-soluble vitamins and Part 2: water-soluble vitamins).
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expert opinion
Phytonutrient intakes in Europe
Fruit and vegetables make an important contribution to health, partly due to the phytonutrient composition, such as carotenoids and polyphenols.
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Topic of the Month
The safety of micronutrients – Part 2: water-soluble vitamins
Insufficient and excessive consumption of nutrients can both increase the risk of damage to health. As intake is increased, the risk of developing a harmful nutrient deficiency falls until the intake reaches an amount that is regarded as adequate (recommended daily amount). Above this amount (tolerable upper intake level or UL) toxic effects may be seen that once more increase the risk of damage to health. How the body reacts to the consumption of specific micronutrients depends on the dosage and on the consumer’s baseline nutrient status. If nutrient levels are already high, increasing consumption is likely to increase the risk of toxicity. With vitamins as with all nutrients: more is not always better. This also applies to water-soluble vitamins, although these do not accumulate in the body to the same degree as the fat-soluble vitamins (see also The safety of micronutrients – Part 1: fat-soluble vitamins).