By Lisa Turner
Yes, a lean, clean diet is key for vital aging. But almost as important as what you eat: how much you eat. Studies show the longest-living populations on the planet consume less food, and slashing calories without cutting crucial nutrients can extend your number of fit, functional years. A significant body of research links caloric restriction with reduced inflammation, improved metabolic health, better cognitive performance and a lower risk of heart disease, cancer, diabetes, dementia and chronic age-related conditions. And other studies suggest minimizing calories not only lengthens lifespan, but also enhances the quality and vitality of those added years.
One reason: normal, essential metabolic processes (including breaking down and digesting foods) generate free radicals, unstable molecules that harm DNA, heighten the risk of disease and speed aging—so less food means fewer damaging free radicals. Periods of fasting also blunts the release of pro-inflammatory chemicals, activates enzymes involved with cellular energy production, and triggers specific physiological changes associated with health and resistance to diseases. In the absence of food, the body shifts into survival mode, prompting cells to maximize efficiency and initiating a process called autophagy—a primitive biological response to perceived starvation. In autophagy, old, damaged components of cells are cleared out and recycled, and new, healthier cells are regenerated. The result: increased energy, improved immunity, less inflammation and better resistance to aging.
Other studies suggest skillfully shrinking food intake encourages weight loss while retaining lean muscle. Caloric restriction has been shown to inhibit the production of new fat cells, making stored fat more accessible and promoting often-significant reductions in weight and body fat—especially dangerous belly fat, associated with metabolic disruptions and greater rates of heart disease, diabetes and stroke. And carefully designed caloric restriction protects muscles from age-related damage, enhancing muscle mass, strength and function.
How to do it safely.
Most research examines the impact of lowering daily caloric intake by about 30 percent—easier that you might think. To eat like a bird, without impacting nutrients: emphasize quality, not quantity. Start by slashing processed foods, refined grains and sugar, linked with heart disease, cognitive decline and other serious conditions. Then focus on nutrient-dense foods rich in fiber, healthy fats and protective antioxidants. Prime choices: leafy greens, cruciferous vegetables, berries, tomatoes, onions, legumes, wild salmon, olive oil, nuts and seeds.
Make restricting calories easier, with tailored plans that fit your lifestyle and personality. One option: alternate day fasting, in which you eliminate food or reduce intake to 500 calories every other day, with normal eating on non-fasting days. Or try intermittent fasting, a regimen that limits daily food consumption to certain periods of time in a distinct pattern; studies show abstaining from eating for 16 hours stimulates autophagy and yields benefits similar to caloric restriction routines. The easiest approach: the 16/8 plan restrains eating to an 8-hour window; for example, you might stop eating at 8 p.m., then abstain from food until noon the following day. To amplify the effects, add exercise. Resistance training stimulates autophagy, and research shows a combo of intermittent fasting and resistance training encourages fat loss while maintaining muscle—keeping your body lean and strong well into your golden years.
Is a chef, nutritionist, researcher and book author with more than 25 years of experience in the field of food, health and nutrition. After earning her master's degree in journalism, she worked for the Los Angeles Times and other leading dailies and weeklies. She is the author of five books on health and nutrition. She is also a second-degree black belt and instructor in Ninjutsu martial arts, and is developing a national program to train young women in self-protection. You can reach Lisa at: inspiredeating.com or follow her on Facebook @inspiredeatingnutrition or Instagram: @inspiredeating