Calorie Restriction (by www.endlesshumanpotential.com)

Info Source: http://www.endlesshumanpotential.com/calorie-restriction.html


Calorie restriction is a dietary regimen, that when applied properly and with all essential nutrients, improves age related health, slows the aging process and promotes longevity in many animals and possibly humans. Research on energy restricted diets over the years has proven that longevity is increased in many animals and fungi such as mice, monkeys, yeast, guinea pigs, rats and some insects. There is also positive research to suggest its effectiveness in slowing the aging process in humans.

Hmmm, maybe this is why vampires live so long. They only drink blood, not many calories there. They are pale and thin normally, however incredibly strong. I’m not kidding either; the vampire myths started with mystical cults where people would only consume blood. They were reported to have lived much longer than other people. Such practices may now be looked upon as total fantasy however it may just be an exaggeration of actual facts. Perhaps calorie resriction played a role.
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What is Calorie Restriction?

Calorie restriction is a dietary regimen that involves restricting total energy intake. How is that different from an eating disorder or starvation? Well starvation involves simply not eating sufficient amounts of food. That results in malnutrition, which in turn results in other issues. By controlling the diet and restricting energy intake while still providing the body with adequate micro-nutrients and energy to complete daily tasks, a person is able to reap the benefits of a well-balanced diet while also benefiting from the proposed benefits of a low calorie diet.

Restricting calories is really quite simple, however it must be done intelligently. It’s easy to just stop eating a lot of food and adjust to being hungry all the time. What is a little more difficult is maintaining low energy intake while still getting all essential nutrients. One always hampers the other. So here are a few tips before we move on…

Eat foods that have a low energy density in comparison to their micro-nutrient content. That means foods like leafy greens, cruciferous vegetables, some meats (especially fish) and many others, just do a bit of research. Avoid foods with empty energy like pasta, rice, bread, noodles, sugar, excess oils and of course fatty foods of any kind.

Do it gradually, don’t jump in the deep end. If you go from being a big eater and then cut down all of a sudden to half the amount of food you will likely experience adverse effects. Gradually cut down your food intake over a period of months.

Get yourself thoroughly checked out beforehand by a doctor. You need to check for deficiencies and anything else that may be adversely effected. It’s no good having diabetes and then finding out you are not sustaining energy levels, which results in severe medical consequences.

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Positive Effects

In human subjects calorie restriction has been shown to lower cholesterol, fasting glucose and blood pressure. In CR energy intake is reduced, however sufficient vitamins, minerals and other important nutrients are still consumed.

Later we will look at why CR might slow the aging process and increase longevity.

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Negative Effects

If a person consumes significantly less calories than is needed to sustain activity levels the person can become underweight. Severe calorie restriction can result in starvation, when it is not carefully monitored. The concept of a calorie restricted diet should not be confused with anorexia nervosa, which is a serious psychological condition resulting in starvation and severe malnutrition.

If a pattern of starvation is repeated for an extended period of time the body can begin to consume lean body tissue along with fat. The combination of starvation and the associated lethargy and loss of muscle mass can result in a lower quality of life and decreased physical activity levels. All of this results in psychological issues, which are then in turn associated with psycho-somatic disorders.

When reducing calorie intake, an individual may also reduce the intake of essential nutrients, especially fat soluble vitamins, which require fat for proper absorption and other nutrients generally associated with high calorie foods such as oils, meat and dairy.

Although calorie restriction is highly recommended by professionals, it needs to be approached with extreme caution. When undertaking a new diet regime of this nature it is advised to arm yourself with as much knowledge as possible and consult a professional. Approached in the right way it can mean the difference between death at 80 and death at 110 or even higher. It is even speculated that CR could lead to life-spans of 125 years old or even more.

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Research

Research on calorie restriction has been conducted over the years and most often leads to the conclusion that it is beneficial and effective in increasing maximum lifespan and life expectancy.

Primates
A study on rhesus macaques showed that CR in rhesus monkeys slows aging and significantly delays age-related diseases such as cancer, diabetes, heart disease and brain atrophy. The monkeys were enrolled in the study between 7 - 14 years of age. At the 20 year point, 80% of the calorie restricted monkeys were still alive compared to less than 50% of the controls.

These results are supportive and somewhat explanatory of earlier findings in the study that showed lower insulin and glucose levels as well as higher insulin sensitivity and LDL profiles.

Mice
Studies in female mice have shown that estrogen receptor-alpha declines in the pre-optic hypothalamus as they age. The mice that were given a calorie restricted diet for the majority of their lives showed higher levels than the mice on normal calorie diets.

Caenorhabditis Elegans
Recent studies in Caenorhabditis Elegans has shown that restriction of glucose metabolism extends lifespan by increasing oxidative stress, which ultimately builds a resistance to oxidative stress. The process is called mitohormesis. Similar effects are possible in humans.
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What reasons could there be for calorie restriction to increase longevity?

There are many theories as to why CR works. I even have a few theories of my own. But before looking at that lets look at what is known.

Mitohormesis
Some researchers are hypothesising that mitohormesis is a primary reason for the life-extending potential of CR. This is due to the likely involvement of mitochondria in cells, which are basically the energy warehouse in cells, responsible for the majority of energy metabolism at the cellular level.

The theory is that calorie restriction induces a low-level stress on the body. This triggers a protective/defensive mechanism where the body actually builds up a resistance to the very stressors that it is experiencing. These stressors are generally experienced anyway, however they are usually at detrimental levels, too much for the body to adapt to and protect against. CR helps to gradually prepare for such responses.

Insulin Signaling
Lowering the concentration of insulin and other hormones associated with insulin such IGF-1 has been shown to increase longevity in mice and other organisms. CR achieves this end indirectly. It has also been shown that if an organism is able to maintain leanness and avoid the storage of excessive adipose tissue that organism is able to increase maximum lifespan.

Combined Reasons
It is unlikely under any circumstances that any one reason can be attributed to its benefits. There is always a desperate search for the one difference that makes the difference. This approach puts on the blinkers and blinds researchers to everything except that which they are currently examining. It is my belief, and the belief of many scientists and other experts, that CR is beneficial at increasing life expectancy and maximum lifespan due to a combination of reasons. Each of these reasons as a stand-alone explanation is weak at best, however combined they strengthen the theories and hold more weight towards the debate.

We have already looked at the known research and the purported reasoning behind the calorie restriction theory, now I plan to break it down and explain in lay terms why I believe CR increases life expectancy.

First off the insulin reason. CR reduces the amount of insulin released in the body and any any other hormones associated with insulin. This alone, outside of CR research, has been shown to cause many changes in the body that lead to longevity. It is likely that people who live a long time have a gene that causes insulin levels to be lower without the adverse effects experienced in diabetes. This benefit is true for those with natural positive insulin responses and those achieving it through calorie restriction.

The insulin reason leads to a number of other things, including some of the other reasons we will include here.
CR reduces LDL cholesterol and increases HDL. This ratio change has a positive effect on the longevity of the heart and the rest of the circulatory system. Taking this and lower insulin concentrations into account without even considering other reasons is likely to show a greatly increased life-expectancy already.

Cancer is one of those things that gets very ugly very fast in a lot of cases. Cancer cells are basically immortal, meaning they can keep growing and surviving indefinitely if there is no intervention.

Over-eating is one of the major indirect causes of cancer-related deaths. It’s not only the fact that some foods consumed in excess can cause certain types of cancer, it also means that excess calories essentially feed the immortal cancer cells.

With a lower calorie diet the cancer cannot grow fast enough and the overall metabolic rate of the body is decreased. With a lower metabolic rate the cancer can either grow very slowly or may not even gain the momentum it needs to survive and in some cases disappears altogether. But perhaps the best part is that lower energy intake allows the body to ward off even getting cancer in the first place, to an extent anyway.
Lower metabolic rate is a major contributor to longevity. The focus is always on a fast metabolism in order to not gain too much weight. This is done through frequent meals and adequate calorie consumption. However weight gain is not an issue with long-term, carefully controlled calorie restriction.

A lower basal metabolic rate leads to less stress on the body while at rest. It’s kind of like suspended animation or a less efficient version of cryogenics. When the body is restricted in energy intake it goes into starvation mode, that response you have been told to avoid. This results in lower body temperature, lower body mass, lower heart rate, decrease in blood pressure etc. All of this in turn allows the body to truly rest when it is resting. This results in less strain and aging on each of the body systems.

Cell division is another reason why calorie restriction may increase longevity. You see, just about all of the body’s cells die out over a period of either days, weeks, months or years. In order to keep you alive they need to keep dividing and creating new cells. This is the cycle of life. The only issue is that each cellular system is suspected of being encoded with an encryption that only allows a finite number of cell divisions.

Aging happens when certain cellular systems can’t keep up production to counter the loss of the dying cells. So someone who dies of old age gradually starts to die their whole life. Every year that you look older and feel older you are closer to age-related death. Sounds morbid, but this is how it works. CR slows down cell division without diminishing regenerative abilities in the body systems.

Finally the super-compensation reason for CR’s effectiveness. When the body is deprived of energy it goes into a slight stress response. This stress response causes the release and production of free-radicals. These free-radicals age the body under most circumstances. However the response caused through CR is a very low-intensity stress that is barely even noticed. This leads to super-compensation via the immune system, which builds tolerance to oxidative stress, one of the body’s major aging causes.

It is my belief that calorie restriction increases longevity through a combination of factors as listed above. This makes more sense. The reason being that oxidative stress resistance alone will have very little effect on lifespan. It is more than oxidative stress that causes age-related death. The same is true for insulin and cholesterol responses. Since these are not the primary reasons for aging it is unrealistic to believe that because CR improves these things that it ultimately increases life-expectancy. Having said that, a combination of these reasons is the most likely explanation for the effects of CR.

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Final Concerns

Calorie restriction may pose some concerns for a lot of people. This may lead to the dismissal of its benefits and create fear that imposes on your desire to practice it.

First of all lowering your total energy consumption by a significant amount can lead to a famine response. This is a natural protective mechanism that occurs in the body. What happens is that is response to lower energy availability the body slows down metabolism leading to increased storage of carbohydrates and fats. Most often the people with the greatest obesity problems are those that try to starve themselves thin only to be overcome with extreme desire for food, which results in over-eating and the gaining of more weight due to the lowered metabolic rate created in the starvation period.

The second concern is that lower energy intake can result in loss of lean body tissue, including muscle mass. This can lead to weakness and a plethora of other problems.

These problems primarily occur in those applying a misguided approach to calorie restriction for reasons other than health and longevity. To put your mind at ease here is a brief explanation of how these two issues can be put to rest.

First off, the famine response. No one wants a slower metabolism where weight gain potential is increased. That would mean you have to work harder to lose weight in future attempts. CR is a long-term lifestyle choice, it is not something you do intermittently while alternating with gorging. Over time your body gets used to the lower energy intake and learns to stabilise metabolism. This results in the more efficient use of energy as it relates to storage rather than expenditure. Yes you will be more sensitive to weight gain but only if you suddenly go back to a high calorie diet. Otherwise you will remain lean and store only the amount of energy your body needs to store. If CR is combined with sufficient exercise your potential for overall fitness, endurance in particular, is greatly increased due to the more efficient use of energy stores.

You may also be concerned about hunger. This is what causes most people to eventually gorge and go back to a high calorie diet after a period of calorie restriction. It takes time for your appetite to adjust, but eventually it will, that’s a guarantee. I went on a low calorie diet many years ago and I don’t have trouble maintaining a lean body profile and I don’t get hungry beyond normal levels. That’s because I gradually adjusted and my appetite now only craves what it essentially needs and nothing more.

As for the muscle loss issue; you may initially feel that you are losing significant amounts of muscle mass. It is normal initially to lose lean body mass. However it need not be great. CR should be approached gradually, not all of a sudden. In this manner your body will make better use of the calories it does consume and will stabilise your metabolism to a point where even a certain amount of muscle gain is possible.

Calorie restriction is an overall healthy choice when it is approached properly. It is not a recommendation to starve yourself thin and deprive yourself of adequate nutrients. What I am recommending is a low calorie diet that still contains all essential nutrients including vitamins and minerals.

Do a little research on the internet into CR and its positive effects. Gather sufficient knowledge of how to implement this dietary choice safely. Don’t jump in head first with no knowledge of how to do it safely and effectively.