Is Intermittent Fasting Really The Ultimate Anti-Aging Diet? by Shin Ohtake
Can intermittent fasting make you healthier, look younger, even help you live longer? According to some researchers and many others that partake in the diet, that is exactly what they claim.
Before I start out talking about intermittent fasting, I think it’s necessary to briefly explain where this whole thing came from. There have been many research studies done on caloric restriction, albeit most of the studies are done on animals, the outcomes have all indicated to providing many health benefits such as low blood sugar levels, low insulin levels, increased insulin sensitivity, low blood pressure… all leading to increased longevity. Although there are no longevity studies done on humans, there is a long term study being done on Rhesus monkeys with very similar results—including increased longevity. That being the case, there’s a strong likelihood that if you were to go on a calorie restricted diet and reduce your calorie intake by 30 - 40%, you would experience all the health benefits seen in studies of the animals (including monkeys)—even possibly living longer.
According to researchers, the mechanisms on how fasting produces these health benefits are still not clear, but there are a few theories as to why this may be:
The first hypothesis suggests that,
...after prolonged dietary restriction, increased resistance to different types of stressors occurs, which permits the cells of many tissues to resist injury induced by genotoxic, metabolic, or oxidative insults
The second hypothesis proposes more specifically that,
...fewer free radicals are produced in the mitochondria of cells, because dietary restriction generally limits energy utilization, which results in less cellular oxidative damage
The third hypothesis proposes that,
CR (calorie restriction) induces intrinsic cellular and organismal programs for adaptation to scarcity, which result in the slowing of metabolic processes such as cell proliferation that contribute to senescence; this hypothesis has been strengthened by findings in yeast
In theory this sounds great, but the problem is that these benefits are only seen when caloric intake is reduced by 30 - 40%, which is pretty drastic and probably not realistic for most of us. Although, according to the people that do live a lifestyle of caloric restriction, the dietary change was gradual and they claim that they do not feel any more hungry than the rest of the society on a normal feeding schedule. I’m sure that’s partly true, since the body has an amazing ability to adapt to pretty much any situation, and this includes drastically reducing your daily caloric intake. But let’s be realistic… If reducing calories was so easy, we wouldn’t be faced with the problem of a balooning overweight population!
There are numerous other problems associated with drastically reducing your calories - severe mood swings, irritability, hostility, depression… Not so good. Is there a better way?
Well, there have been a number of studies done on another method that showed similar health benefits of caloric restriction without having to reduce calories. This method is called intermittent fasting (commonly referred to as “IF”). Intermittent fasting, unlike regular fasting, and as the name implies involves a period of fasting followed by a period of feeding. A regular fast involves a much longer period of not eating. There are many different ways to incorporate intermittent fasting, the most popular being fasting and feeding on alternate days. That means you would eat one day and fast the next day. If that seems too extreme to you, another popular method is fasting all day and eating only at night. For instance you’d eat from 5 - 10 pm every night followed by 19 hours of fasting.
In studies comparing animals on intermittent fasting (fed every other day) and animals on an “ad libitum” feeding schedule (eating whatever and whenever they wanted all through out the day), they found that animals on intermittent fasting ate double the amount of calories than those on the ad libitum feeding schedule. This meant that both groups ended up with the same weekly caloric intake. But, the animals on intermittent fasting still showed all of the health benefits seen in animals on a caloric restriction diet… In a nutshell, they got all the benefits without skimping on their calories.
In addition, the animals on the intermittent fasting diet increased their BDNF (brian-derived neurotrophic factor) compared to the animals on the calorie restricted diet. BDNF helps grow new nerve cells in the brain that helps protect it from harmful stressors. Even more, it somehow increases insulin sensitivity (in animals) and lowers levels of depression (seen in humans) as well as improving cognitive abilities.
The idea of intermittent fasting also goes along nicely with people that are already following a Paleo Diet. This diet basically promotes what we ate during the Paleolithic era, with lots of animal meat, fish, vegetables, some fruits and a little starch. No processed food and sugars. And since we were hunters, we hunted during the day to catch our meal and feast at night. So it probably wasn’t out of the ordinary to only eat two meals every three days. If that was the case, your body may have been used to a feast and famine type of feeding schedule. That would mean your body was made to intermittently fast.
Then there’s the concept of “autophagy”. I know I’m getting technical on you today, but bare with me… if your into looking, feeling and staying younger, you’ll find this information quite interesting. Autophagy is a cellular process that occurs during states of low energy such as that seen with fasting. Autophagy literally means self consumption. During low energy states the cell actually eats itself and the internal material is recycled and used to fuel other cellular processes. It’s basically cellular energy management. So during states of fasting, autophagy takes place to reduce the number of cells, reuse and recycle the materials from the cell for fuel. The neat thing is that newer younger cells are much more adept to this process compared to older cells, which is why older cells end up accumulating, and contributing to aging. This means that regular states of fasting would keep your cells younger and more efficient.
So let’s recap… Intermittent fasting allows you to eat whatever you want and however much you want during the feeding period and still get all the benefits of being on a caloric restriction diet. Plus, you produce more BDNF which protects your brain from harmful stressors, while making you happier and more sensitive to insulin thereby helping you lose more weight! And ultimately, it may even help you look, feel and stay younger!
Does all of this sound too good to be true? Is this type of lifestyle realistic? Is this a long term plan? Are all health benefits claimed true, since most of the studies are done on animals and only few studies have been done on humans? With no large scale or long term studies done on humans, there’s no solid conclusions on the effectiveness of the diet, but it’s intriguing enough to try it out, as evidenced by a large population of people that have either tried it or are on it. But before you dump the traditional 6 meals a day eating plan, here are a few more facts about intermittent fasting, taken from a small group of studies done on humans.
If you’re only eating once a day, does your hunger level ever subside? According to a study done on a small group of individuals…no. In fact, this study claimed that eating 3 times a day substantially controlled hunger levels compared to eating only once a day - even when the same number of calories were consumed. The other problem they found was that when you’re only eating once a day, you have the tendency to gorge and over eat, often exceeding the total calories you would normally consume when eating more frequently.
Some of the positive effects of intermittent fasting are insulin sensitivity, fat loss and weight loss. While some studies did show a marked improvement in insulin sensitivity, it also came with an increase in fat uptake sensitivity. They also found women on intermittent fasting developed glucose intolerance where as men did not. And lastly, weight loss did take place amongst the people studied on intermittent fasting, but it was due to calorie deficits caused by not being able to consume as much calories during the feeding period. This may be a good thing, except it also increased hunger, and the group suffered irritability and increase thoughts about food as a consequence.
The level of BDNF produced from intermittent fasting is another beneficial factor, but recent studies have found that exercise intensity is heavily correlated with an increase in BDNF production. Some studies say that high intensity exercises can produce just as much BDNF as intermittent fasting.
There seems to be strong evidence that intermittent fasting improves cardiovascular health, but if your including weight bearing exercises as part of your workout, studies found muscles had a much harder time recovering in a fasted state then in a non-fasted state. Performing weight bearing exercises during low energy states also seemed to interfere with protein synthesis, which would indicate a disruption in muscle development. All that work and nothing to show for it…
Some studies are suggesting that many of the health benefits seen from intermittent fasting and caloric restriction can also be achieved from a proper exercise regimen without any calorie reduction or change in feeding schedule.
Lastly, the other main concern is that many of the health benefits are from studies done on animals and not humans. In fact, only a few studies have been done on humans with results not nearly as significant or as conclusive as the studies on animals. That being said, more human studies are needed before any real conclusions can be made.
I do know from personal experience, that often times conclusive scientific studies come much later than what professionals in the field deduce from “applied experiments” much earlier. Partly, I think we’re always on the look out for the next great thing and just like kids in a candy store, we can’t wait to try it out and see for ourselves if it works or not. That being said, scientific studies are absolutely essential and are needed to provide real proof to all of our applied theories.
So, does intermittent fasting fall into the category of applied experiment? Absolutely, in my opinion. Does it work? Some swear by it, some not. But I think it’s worth a look.
Shin Ohtake is the author of the world-famous fitness program, MAX Workouts. To learn more about how you can get ultra lean and toned with shorter workouts, visit http://www.MaxWorkouts.com