Besides synthesizing nutritive substances (proteins, fats and carbohydrates) for energy and growth, plants produce numerous non-energetic so-called secondary metabolites (mainly polyphenols) that allow them to protect themselves against infections and other types of hostile environments. Interestingly, these polyphenols often provide cells with valuable bioactive properties for the maintenance of their functions and homeostasis (signaling, gene regulation, protection against acquired or infectious diseases, etc.) both in humans and animals.
Approximately 40 micronutrients are required in the human diet. Deficiency of vitamins B12, folic acid, B6, niacin, C, or E, or iron, or zinc, appears to mimic radiation in damaging DNA by causing single- and double-strand breaks, oxidative lesions, or both. The percentage of the US population that has a low intake (< 50% of the RDA) for each of these eight micronutrients ranges from 2% to > or = 20%; half of the population may be deficient in at least one of these micronutrients.
An ideal diet is one that promotes optimal health and longevity. Throughout history, human societies have developed varieties of dietary patterns based on available food plants and animals that successfully supported growth and reproduction. As economies changed from scarcity to abundance, principal diet-related diseases have shifted from nutrient deficiencies to chronic diseases related to dietary excesses. This shift has led to increasing scientific consensus that eating more plant foods but fewer animal foods would best promote health.
BACKGROUND: In studies from Italy and Greece, a Mediterranean dietary pattern was shown to favorably affect life expectancy in the elderly population. This pattern is thought to reduce the risk of cancer in addition to being cardioprotective.
We conducted a 5-year cohort study among 162 self-sufficient residents in a public home for the elderly in Rome, Italy, to evaluate the association between the consumption of specific food groups and nutrients and overall 5-year survival. We used a validated, semiquantitative food-frequency questionnaire to assess diet at baseline.
Mortality statistics from the WHO database covering the period 1960 to 1990 have provided intriguing evidence that something unusual has been affecting in a beneficial way the health of the Mediterranean population. In recent papers, which evaluated the evidence accumulated over the last three decades, it was concluded that the traditional Mediterranean diet meets several important criteria for a healthy diet. Direct evidence in support of the beneficial properties of the Mediterranean diet has also become available.
Aging is a complex biological process, which usually is accompanied by changes in socio-economic status, which may have a great impact on the physical and nutritional status of the elderly. Decreased food intake and a sedentary lifestyle in the growing numbers of the elderly increase their risk for malnutrition, decline of bodily functions and developing chronic diseases. Oxidative stress is believed to be an important factor in aging and many age-associated degenerative diseases.