eat less, live to a hundred twenty?

You know that a new diet is now a trend when it appears on daytime talk shows. All the big diet fads got their start this way and now, following in their footsteps is something known as calorie restriction. It’s exactly what it sounds like. Practitioners will limit the nutritional value of what they eat on a daily basis to under 2,000 calories. Some go as extreme as 1,600 calories, about 80% of what humans are supposed to eat. And being on daytime television, calorie counters are making bold claims about what their diet can do for you.

Dr. Mehmet Oz, a staple of some of daytime’s biggest talk shows, recently made the claim that extreme calorie counting will let some people live to 120 and went as far as declaring that one particular practitioner of this diet trend, Joe Cordell, could live to see his 150th birthday. Don’t start wondering if you could get by on an apple a day just yet though. When it comes to getting your nutritional advice from talk shows, I have a simple suggestion. Don’t.

Rather than dig into the details and discussing the pros and cons of the next fad to sell a gazillion diet books, these shows usually present what equates to an infomercial for whatever idea the thriving weight loss industry wants to embrace that month. But believe it or not, there actually have been studies on the concept of calorie restriction and serious academics have found a number of benefits, so much of the underlying science is solid. However, like all good things, calorie counting can be taken to very dangerous extremes and cause more harm than good.

why and how would calorie restriction work?

Human bodies work best when we’re lean and have just enough food to provide us will all of the nutrients and vitamins we need to function. Anything more than that becomes excess calories and when coupled with a sedentary lifestyle, become excess fat. Being overweight carries many well known health problems such as high levels of low density lipoproteins, or LDL cholesterol. That’s the bad kind. The kind that clogs arteries and causes heart disease. Too much bulk also causes hypertension, can help trigger diabetes and reduces lifespan.

By restricting yourself to a relatively small number of calories and carefully monitoring what you eat and how, you could avoid the causes of obesity, sidestep the problems with ingesting empty calories and put less stress on your body. The result is a prolonged lifespan. But by how much? Could anyone really live to 150 on 1,950 calories a day and is restricting yourself to 1,600 calories a potential time bomb? The most probable answers are no and yes, respectively.

According to our current understanding of medicine, if every disease were curable and we had some of the healthiest lives possible, we’d all be living somewhere around 120 years. However, not every disease is curable and one of the key processes behind aging is the drastic decline in our immune systems. People who live to be extremely old (95+) will actually die of frailty since their bodies are so deteriorated by the ravages of time, just about any serious stress would kill them.

There’s no kill switch in nature, so frailty of old age serves as the finishing blow to a living thing and that’s something extremely difficult to counter with calorie restriction. And even the healthiest diet wouldn’t protect you from all cancers, especially if they’re hereditary. A far more realistic claim is to say that you might get an extra 10 to 15 years and your quality of live would improve drastically since your body would be lean, mean and healthy. Any more time on Earth than that would just be icing on the cake. Which you probably shouldn’t eat too much of.

is there a downside to caloric restriction?

Conversely, you don’t what to limit yourself too much. After all, cutting down calories to a drastic level means that you’re starting to cut into essential vitamins and nutrients which could affect how your body metabolizes its basic fuels. Hair and nails could grow slower, lacking the materials to regenerate themselves. Blood pressure could fall below normal and you could slip into the underweight category, starving your immune system of what it needs to effectively do its job. Being severely underweight would actually shorten your lifespan and come with its own set of complications.

For example, while we tend to associate body fat with heart disease and a very high percentage of it is bad news, we do need at least some. Too little of it and fat soluble vitamins don’t get properly absorbed into our bodies. In effect, you could calorie restrict your way into semi-starvation and into an early grave, exactly the opposite of what you want to do. I know there are examples of people who only consume 1,600 calories for a day for a year and they seem just fine, but when we’re talking about life-extension studies, we really need to track them over many decades, not just their first year or two.

So if you want to take on calorie restriction to help prolong your life, there’s some science that would support your decision and it probably will be good for you if you stick to it for years. But don’t get overzealous and starve yourself on just a few calories a day, expecting to live beyond the ripe old age of 150 by virtue of eating less.