Nutritional requirements for the elderly in India: A status paper

Advances in the medical field and healthcare sector during the last few decades have resulted in increased longevity. Increased lifespans have in turn led to a rapid global rise of the elderly population. However, ensuring the health and quality of life, especially in the context of chronic age-related ailments, among the growing geriatric population is a challenge. Ageing is associated with several changes in body composition including a decline in the lean body mass usually accompanied by an increase in body fat content which have a bearing on the nutrient requirements for the elderly. The nutrient requirements currently recommended for Indian adults are primarily computed using a factorial approach, that considers the cumulative loss of nutrients and is adjusted for optimal body weights and bioavailability. It is logical that physiological and metabolic changes associated with ageing influence several of these factors: body weight, lean mass, energy expenditure, nutrient retention and bioavailability and thus alter nutrient requirements compared to the adult population. Acknowledging these age-related changes, some international organizations have suggested nutrient requirements specific to the elderly. Given the contextual differences in physiology, caution needs to be exercised in adopting these guidelines for the Indian elderly. In addition, in the Indian context, there is sparse information on the diet and nutrient intakes vis-à-vis nutritional status and physiology of the elderly. This status paper highlights some of the pertinent issues related to nutritional requirements for the elderly that advocate a need for deriving nutritional requirements for the elderly in India

Benefits of early glycemic control by insulin on sensory neuropathy and cataract in diabetic rats.

While there is an emphasis on the early glycemic control for its long-term benefits in preventing microvascular complications of diabetes, the biochemical mechanisms responsible for the long-lasting effects are not clearly understood. Therefore the impact of early insulin (EI) versus late insulin (LI) treatment on diabetic sensory neuropathy and cataract in streptozotocin-induced diabetic Wistar male rats were evaluated. EI group received insulin (2.5 IU/animal, once daily) treatment from day 1 to 90 while LI group received insulin from day 60 to 90. Early insulin treatment significantly reduced the biochemical markers like glucose, triglyceride, glycated hemoglobin, thiobarbituric acid reactive substances, advanced glycation end products and ratio of reduced glutathione and oxidized glutathione in diabetic rats. The late insulin treatment failed to resist the biochemical changes in diabetic rats. Diabetic rats developed sensory neuropathy as evidenced by mechanical and thermal hyperalgesia and showed a higher incidence and severity of cataract as revealed by slit lamp examination. Early insulin treatment protected the rats from the development of neuropathy and cataract, but late insulin administration failed to do so. The results demonstrate the benefits of early glycemic control in preventing neuropathy and cataract development in diabetic rats.

Insulin resistance mediated biochemical alterations in eye lens of neonatal streptozotocin-induced diabetic rat.

Cataract, the leading cause of blindness worldwide, is associated with many risk factors including diabetes. Impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) states are associated with pre-diabetes and insulin resistance. This condition subsequently leads to the development of type-2 diabetes. Epidemiological studies indicated that not only diabetes but IGT/IFG will also lead to the development of microvascular disorders and cataract. However, there are no studies on the mechanism of insulin resistance induced changes in the eye lens. In the present study, IGT/IFG-induced changes in lens using neonatal-streptozotocin (nSTZ) rat model have been investigated. Though, nSTZ rats showed the signs of IGT and insulin resistance starting from two months old, they did not develop cataract even at the age of 8-months. However, biochemical analysis indicates a three-fold increase in sorbitol levels in nSTZ lens upon prolonged (6-months) IGT and insulin resistance. Also there was an increase in lipid peroxidation and alterations in antioxidant enzymes. Results of this study showed that activation of polyol pathway and increased oxidative stress, commonly associated with long-term complications of diabetes, have been observed in eye lens due to prolonged IGT and insulin resistance which may lead to cataract.

Cumulative antioxidant defense against oxidative challenge in galactose-induced cataractogenesis in Wistar rats.

Natural dietary ingredients are known for their antioxidant activity. Of such, curcumin, the active principle of turmeric, at 0.01% in the diet proved as pro-oxidative in galactose-induced cataract in vivo. The purpose of this study was to investigate the effect of vitamin E (VE), a well-known antioxidant, in combination with curcumin on the onset and maturation of galactose induced cataract. Periodic slit-lamp microscope examination indicated that in combination with vitamin-E, 0.01% curcumin (G-IV) delayed the onset and maturation of galactose-induced cataract. Biochemical analyses revealed that combined treatment of 0.01% curcumin and vitamin-E diet exhibited an efficient antioxidant effect, as it inhibited lipid peroxidation and contributed to a distinct rise in reduced glutathione content. The results indicate that natural dietary ingredients are effective in combination rather than the individual administration as they are complementing each other in reducing the risk of galactose induced cataract.