There has been an huge rise in the proportion of older people in the world during the past century - in 1950 only 8% of the world’s population was over 60 years old but that proportion will be up to 21% by 2050.
Ageing is associated with an increased risk of chronic disease and disability. The most widespread conditions affecting older people include: hypertension (high blood pressure), vascular disease, congestive heart failure, coronary heart disease, dementia, arthritis, osteoporosis, diabetes, glaucoma, macular degeneration and impaired immunity.
Ageing affects everybody in different ways, but there are three main contributions to healthy ageing:
- genetics and family history
- lifestyle practices and exercise
- diet and nutrition
The first of these three factors is 100% out of our control, but the remaining two are within our powers to influence and modify so establishing healthy lifestyle practices, including consuming a healthier diet becomes all more important as we age.
The role of calcium and vitamin D has been associated with its important function in bone metabolism and the prevention of osteoporosis. In recent years there has been increased research attention placed on the non-skeletal roles of these nutrients. For example vitamin D has been implicated in a variety of diseases including diabetes.
A prominent theory of ageing and chronic disease has been the “free radical theory” in which a lifelong accumulation of cell damage due to free radicals leads to an increased risk of disease and disability. It has been thought, therefore, that diets rich in antioxidants, such as vitamin E and vitamin C and many polyphenol compounds found in fruits and vegetables will help combat free radical damage and improve health.
Many of the plant based antioxidant components are being identified and isolated for use in supplements. As research increases, additional benefits of these components are being identified. The curcuminoid polyphenols, which are the primary polyphenols in the underground stem of the turmeric plant (Curcuma longa) and are responsible for its yellow colour, have potent antioxidant and anti-inflammatory properties. These properties have led to investigations into curcumins' impact in preventing cognitive decline relating to Alzheimer’s disease. There has been a dramatic increase in research into the benefits of these ingredients, with more than 2,400 articles published in the past decade.
Green tea polyphenols have been shown to have powerful antioxidant and anti-inflammatory benefits. The most famous of these is Epigallocatechin-3-gallate (EGCG). EGCG is found in high concentrations in green tea. As a member of the catechin family of compounds, it has antioxidant properties, but it also has other biochemical effects in cells.
Grape seed extract (GSE) is a concentrated source of polyphenols. These resemble the catechins of green tea in basic molecular structure with the exception that components in grape seed extract reach a larger molecular size. Although clinical research on GSE for inflammation is not as advanced as that for the curcumins, and green tea catechins, there is abundant evidence suggesting GSE alsos has applications aimed at protecting against oxidative stress, aiding circulation, in addition to its general anti-inflammatory effects.
Lutein and zeaxanthin are members of the carotenoid family of compounds and are found abundantly in green leafy vegetables. These carotenoids have properties beneficial to health and are found in high concentrations in the macula of the eye, which is responsible for central vision. Macular degeneration is a common problem in the elderly and is among the four leading eye diseases found in this population. Supplementation of patients with early signs of macular degeneration with lutein and zeaxanthin has been shown to be beneficial. In addition, consumption of diets rich in lutein and zeaxanthin have been found in a recent meta-analysis to be associated with a reduction in the risk of developing late stage macular degeneration.
Plant Sterols and Stanols
Plant sterols and stanols are found naturally in small amounts in many plant-based foods. These compounds have cholesterol-lowering properties resulting from the inhibition of cholesterol absorption, and manufacturers have started using them as food fortificants to help lower blood cholesterol and reduce the risk of heart disease. Since heart disease is a common condition in older people, it would be sensible for the older population to consider using plant stanol/sterol-enriched food products as part of a healthy diet.
There has been a resurgence in interest about the B-vitamins because of their possible roles in heart disease and cognitive impairment.
Vitamin B6, Vitamin B12 and folate are three important B-vitamins that are involved in metabolic cycles that supply the body with methyl groups (one-carbon metabolites) that are important to many functions in the body, including homocysteine metabolism, a potential risk factor for heart disease.
Omega 3 Fatty Acids
Omega-3 fatty acids are found in fish oil and in some plants, such as flaxseed. Omega-3 fatty acids are known to have anti-inflammatory effects and to lower blood triglycerides and have been suggested to have a positive effect in patients suffering from recent myocardial infarction (heart attack) or heart failure. The Japan EPA Lipid Intervention Study (JELIS) found a 19% reduction in the risk of coronary heart disease and a significant reduction in recurrent stroke after long- term use of pure eicosapentaenoic acid (EPA) in Japanese patients with hypercholesterolemia.
Higher circulating long-chain omega-3 fatty acids have also been shown to be associated with a lower risk of congestive heart failure in a prospective cohort study.
Another interesting finding concerning omega-3 fatty acids is that female health professionals consuming higher intakes of EPA and DHA had a lower incidence of age-related macular degeneration.
Glucosamine, Chondroitin and Collagen
Arthritis refers to an inflammation of the joints. The most common type of arthritis is osteoarthritis, often called ‘wear-and tear’ arthritis, which may manifest as morning stiffness and pain in the hips and knees. During movement, the cartilage that surrounds the ends of bones in joints is subject to breaking down and must be repaired. Cartilage is composed of type II collagen. Glucosamine and chondroitin are two molecules that are found in cartilage and oral consumption of these building blocks of cartilage are believed to be beneficial in reducing pain and protecting bone cartilage. Although the effectiveness of these compounds in osteoarthritis remains uncertain a recent randomized, double-blind clinical trial in Japanese subjects with symptomatic knee osteoarthritis found an improvement in symptoms in those receiving a combination of glucosamine hydrochloride, chondroitin sulfate and quercetin glycosides compared to the receiving placebo.
A study in Belgium found in a follow up of subjects that had previously been enrolled in clinical trials of glucosamine sulfate for knee osteoarthritis and had received treatment for at least 12 months that the glucosamine treatment group were 57% less likely to require total joint replacement surgery compared to the placebo group.
The large intestine is normally filled with a large range of different bacteria, which are believed to play an important role in maintaining health. It is believed that large populations of friendly bacteria aid in keeping the growth of unfriendly pathogenic bacteria and yeast at bay. It is believed that supplying the body with good bacteria (probiotics), such as those from the Lactobacillis and Bifidobacterium families, can help restore the correct bacterial balance. Prebotics are non-digestible food carbohydrates that can enter the large intestine and act as nutritional supplements to stimulate the growth of certain intestinal bacteria. The role of intestinal bacteria in health is an active and exciting area of current research which is still in its infancy.
Potassium is an essential mineral nutrient that plays a number of critical roles in the body. Research has shown that diets high in fruits and vegetables are associated with a reduced risk of hypertension (high blood pressure), which may be due to the beneficial effects of dietary potassium on blood pressure.
Zinc is an essential trace element that is biochemically involved in a wide variety of reactions and has important effects on DNA synthesis, cell proliferation and differentiation. Immune function is compromised in zinc deficiency and zinc supplementation along with antioxidants may play a role in protecting people from macular degeneration.
Coenzyme Q10 plays an important role in aerobic respiration in the mitochondria of the cell and is involved in the generation of ATP, which is used as an energy source by the cell. Coenzyme Q10 is also a powerful antioxidant that can reduce oxidative stress. Supplementation with coenzyme Q10 has also been found to have an anti-inflammatory effect by reducing the inflammatory marker IL-6 in patients with coronary artery disease. Another study has found that coenzyme Q10 supplementation improves endothelial function in patients with heart disease.