Numerous studies have shown that lowering your caloric intake may slow down aging, help prevent age-related chronic diseases, and extend your life. As you age, your levels of glucose, insulin and triglycerides tend to gradually creep upward.
A 2010 study examined the effects of a high-fat diet on typical markers of aging. Study participants were given a high-fat, low-carbohydrate diet with adequate protein, and the results were health improvements across the board. Serum leptin decreased by an average of eight percent, insulin by 48 percent, fasting glucose by 40 percent, triglycerides by nearly eight percent, and free T3 (thyroid hormone) by almost six percent.
What we know now about calorie restriction is that, in animals, it reduces metabolic rate and oxidative stress, and it alters neuroendocrine and sympathetic nervous system function. We also know that calorie restriction improves insulin sensitivity, and high insulin levels accelerate aging.