Nobody wants to look old. The endless variety of anti-aging creams on the market claiming they can turn back or at least halt your body’s clock are proof of that. Most people will try anything to stop or at least slow down aging if given a chance. In addition to beauty products, many new diets have surfaced that promote how what you put inside your body is equally as important as what you put on it. As a result, food has become an essential element of anti-aging treatment.
Of course, scientists have questioned the anti-aging diets’ efficacy. So several have studied the effects of the most popular ones on rodents to see if their benefits hold merit. Recently, a team of researchers from Pennington Biomedical Research Center and the University of Washington in Louisiana weighed in on the matter in a review article detailing these studies.
Their research included calorie restriction, intermitted fasting, and the ketogenic diet. They found that all the diets delivered promising results in the animal models but that more research is needed to confirm if the results would be the same in humans. They didn’t find any adequately controlled, long-term studies in humans demonstrating that these diets produce longevity benefits.
The Review
Calorie restriction, intermitted fasting, and the ketogenic diet are widely hyped to delay age-related functional declines and disease, resulting in an extended lifespan.
With caloric restriction, one cuts calories while still maintaining good nutrition. This diet has the most credibility. Studies found that rodents generally lived healthier and longer lives by reducing daily caloric intake by 20-50% while maintaining an adequate intake of vitamins and minerals. The animals on this diet had a reduced incidence of disease compared to normally-fed controls.
With intermittent fasting, one takes at least a 24-hour break between meals. This diet usually involves gaps between eating, lasting 24-48 hours. It also delivers robust results, but it’s possible that the benefits merely arise from eating less. Meaning, it’s hard to know if it’s intermittent fasting at work or calorie restriction.
With the ketogenic diet, the dieter restricts carbohydrate intake to approximately 10% or less of daily calories so that the body produces and utilizes ketone bodies for fuel instead of sugary glucose. Unfortunately, this diet only had a couple of rodent studies, so the review authors caution there isn’t enough research to back its reliability. Nevertheless, of the studies, the rodents on a ketogenic diet did experience a boost in memory and motor function and slightly extended lifespans.
Are These Diets Good For Everyone?
The authors suggest people shouldn’t rely too heavily on these diets when deciding how to eat. They wrote:
Despite their recent popularization, there is not yet strong evidence that any of the anti-aging diets studied in laboratory animals have substantial long-term health benefits in nonobese humans.
They also caution against adopting such intensive diets because they can bring about substantial biological effects that benefit some while harming others. Therefore, they recommend that people interested in trying these diets see a medical professional or nutrition expert first and throughout the process for guidance. Inadequate attention to detail can leave the dieter nutritionally deficient.
They concluded:
Although caloric restriction and other diets hold promise, additional data from carefully controlled studies are needed before broadly recommending or implementing these diets, or other interventions, for otherwise healthy people.
Since these diets reduce caloric intake so drastically, the calories the dieter does consume are all as nutritional as possible.
Intriguing Anecdotes
The review gives an example, sort of like a case study, that highlights calorie restriction working in the real world. The Okinawans inhabit a cluster of small islands off the Japanese coast. It’s estimated that they consume about 20% fewer calories than mainland Japanese and get approximately 85% of their calories from carbohydrates.
The authors wrote:
[Historically, they have also had the] longest life expectancy at birth and highest centenarian prevalence in the world, with remarkably low rates of age-associated diseases, such as cancer, heart and cardiovascular disease, and diabetes.
However, just because this diet works for many Okinawans doesn’t mean it will work for everyone in the world.
