Longevity and the Benefits of Fasting

Share it

by Rima Martin

Fun Fact: an article in Cell Stem Cell, published by Elsevier’s Cell Press, found that a simple dietary intervention — periodic fasting — may combat both chemotherapy-induced and aging-related changes in immune cell function by replenishing stem cells in the blood.


There is hardly a person on this planet who does not cherish the moment their taste buds make contact with good food or a refreshing beverage. We are creatures of comfort, and this sometimes leads to indulgence. Unfortunately these indulgences can come with hidden dangers. Today there are many people who fast to manage their body weight, but it is nothing new; it has been practiced since ancient times for physical and spiritual purification.

Fasting is just the restriction of specific foods for set periods of time. When some people hear the word they dismiss it, wrongly assuming only monks and yogis fast. Research into longevity genes and the ways different schemes of caloric restriction affect their expression is changing this view. Fasting is and has been the norm in many societies throughout history. If fasting is something you would like to try, you must first decide on which approach is best for you.

Occasional Short Fasts is where I recommend people start. These can last 6, 12, or 24 hours. This means you could fast for 6 hours straight at any time of the day, although mornings are generally preferred. As one can imagine, this approach offers a great deal of flexibility. Once you decide what you are abstaining from, you can plan accordingly. For example, if you are abstaining from milk products, make sure there are no dairy temptations around you.

Intermittent Fasts – With this type of fasting, you cycle between periods of eating and fasting. It’s not about what food you should eat but when you should eat. Intermittent fasting involves daily 16 hour fasts or fasting for 24 hours twice a week. Some people use the 16/8 Method. This involves skipping breakfast and restricting the window of consumption to 8 hours. This is followed by a 16 hour fast  More than another fitness fade, it is also a means of organizing and simplifying your life.

Water Fasting is close to my heart. After the cells use up the glucose from your last meal your body has to find another source of energy, which means glycogen (a polysaccharide stored in the liver and muscle tissue) must be broken down to supply it. After the glycogen is used up, the cells begin burning fatty acids for energy.

Extended Fasts is a sure but hard path. It is probably the second most extreme form of fasting, since you are expected to go 2-3 days without eating. The most extreme fasting would be dry fasting during which you don’t consume anything, including water. During a long fast, your body stays in ketosis for an extended period. It suppresses hunger and lets you  get your mind off food.

I have fasted for three days at a time. I usually water fast (consuming only water throughout the fasting sessions)  The absence of calories for three days sets the body on edge, but also maximizes immunity against diseases and encourages various cellular repair processes. Still don’t believe me? Let’s look at some facts and figures gleaned from the cutting edge of longevity science.

How Fasting Changes Our Bodies

Fasting remains a part of every major religion in the world. Jesus Christ, the yogis of India, Buddha and the prophet Muhammad all shared a common belief in the healing power of fasting. In spiritual terms, it is considered cleansing or purificatory, but practically, it amounts to the same thing. Dietary alterations can go a long way to counteracting the ravages of time.

The body undergoes many positive changes during fasting. While fasting, our body generates its own energy by burning stored resources made from excess fats, carbs, and sugars to produce energy. The liver then converts fats into chemicals called ketone bodies, which are then used as an energy source. Chemicals and toxins are absorbed from the food are then stored as fat reserves and released during fasting.

Medical studies show that during a fast abnormal tissues growths, like tumors, become more susceptible to remission. One of the first major studies took place in 1945 and showed that intermittent fasting not only prolonged life but reduced the prevalence of breast cancer tumors in rats. A more recent study in 2009 proved the practice can even reduce the severity of side effects of high-dose chemotherapy.  Valter Longo, associate professor of gerontology and biology at USC, was part of the 2009 study. His study results were explained this way:

“In essence, these cells are waiting out the lean period, much like hibernating animals. But cancerous tumors respond differently to starvation; they do not stop growing, nor do they hibernate because their genetic pathways are stuck in an ‘on’ mode. Longo realized the starvation response might differentiate healthy cells from cancer cells by their increased stress resistance and that healthy cells might withstand much more chemotherapy than cancer cells.”

A few years later, Longo reported that fasting alone was enough to treat many types of cancer in mice. Because the body’s healthy cells were in this hibernation mode, the cancer cells tried to find other ways to divide and spread, without  much success.

Other processes that sustain the foundational infrastructure of the body are fostered by fasting, which means the production anti-aging growth hormones is increased. Now we are getting somewhere! Has your interest piqued yet? Our bodies are resilient and quite capable of healing themselves.

Unfortunately, we may internally mutilate our bodies with unhealthy food. This interferes with our bodies innate potential to rebuild cells and lengthen our lifespans. By encouraging regeneration, fasting results in healthier cells, tissues, and organs. There’s a tentative hypothesis circulating among  doctors and nutritionists that fasting allows the body to concentrate its resources on ridding itself of diseases and poisons rather than using them to digest food.

Scientists and Doctors who Support CR and Fasting

Clive Maine McCay – An American biochemist, gerontologist, nutritionist and professor, discovered CR increases the lifespans of rats in 1934. Fifty years later his work was recognized as a viable research model for aging.

Valter Longo – An Italian biogerontologist and a cell biologist who serves as the director of USC Longevity Institute. He has published several articles on calorie restrictions and its longevity benefits.

Dr Kris Verburgh – a medical doctor, researcher and author. By the age of 25 he had written three books. His writes, “ageing is a very complex process. The rate of ageing is influenced by our genes, our environment, and more specifically, by how and what we eat. Powerful interventions that slow down the ageing process will come to see the light in the coming decades. For now, the most potent tool at our disposal to impact the rate of ageing, is our diet.”

Calorie Restriction

“Have breakfast like a king, lunch like prince, and dinner like a beggar.” Not having to cook large meals in the evening not only saves time but also paves a path for better eating habits.

If fasting seems or sounds tough, a more trendy approach to healthy eating and cellular repair is Calorie Restriction (CR). According to Dr Kris Verburgh, an author, medical doctor, and gerontological researcher, Calorie Restriction is the practice of limiting dietary energy intake. In CR energy intake is minimized, but sufficient quantities of various micronutrients must still be consumed. For example, males between 19-30 need about 2600 calories a day. During CR they would eat 2000 calories daily. The average lifespan in developed nations is approximately  80 years and the maximum lifespan is approximately 120 years.

CR works at the molecular level by regulating transcription factors. While the average lifespan is determined by genetic factors and lifestyle choices, there are few interventions known to science that can increase maximum lifespan in model organisms. CR and rapamycin (a compound that has successfully extended maximum mouse lifespans – even brief rapamycin treatment in middle-aged mice lived up to 60 percent longer than the control group) if you practice CR, your body will generally think it must prepare itself to deal with scarcity. CR inhibits growth and promotes maintenance. This may not sound like an entirely good thing, but if growth (constant production and replacement of cells and proteins and DNA, etc), is inhibited via CR, then we age less rapidly.

If we eat like we normally do, with an overabundance of food, then the body will no longer go into a “power-saving mode.” Therefore, plenty of proteins are created, mitochondria (the energy power plants of our cells) run at full speed creating free radicals. These cellular activities cause the body to age faster. CR is very beneficial to our overall health. There are extensive benefits to CR which will be discussed later in this article. However, when commencing calorie restriction, people must take caution not to become deficient in essential nutrients. CR is most certainly not suitable for everyone especially for pregnant women, children, and people with certain illnesses.

The crystallographic structure of yeast sir2.


Many scientists believe  CR activates a longevity factor belonging to a class of genes called Sirtuins (SIRT1). The following information comes from primarily from a paper somewhat dramatically titled Unlocking the Secrets of Longevity Genes. A few years ago scientists believed aging is not just deterioration, but an active continuation of an organism’s preprogrammed developmental cycle. These two ideas turned out to be complimentary.

By optimizing the body’s functions for survival, these genes maximize an animal’s chances of enduring a famine. If they are activated over prolonged periods, they can dramatically extend the organism’s lifespan. Scientists believe CR is a biological stressor, and like natural food scarcity it induces a defensive response. In mammals its reported effects include changes in repair, energy production, and the activation of programmed cell death, also called apoptosis. The survival mechanisms turned on by CR stalls the progressive damage suffered at the cellular level on a daily basis.  This is seen as a breakthrough when it comes to anti-aging, as the longer we keep our cells and organs functioning, the longer we are able to healthfully and happily live.

Another critical process influenced by Sirtuins is inflammation. Inflammation has been connected to cancer, arthritis, heart disease, diabetes, and assorted neurodegenerative disorders. SIRT1 is activated by NAD+, an important substrate in energy and oxidation reactions, so SIRT1 acts as an energy and redox sensor. Nicotinamide adenine dinucleotide (NAD+) is a classical coenzyme; it plays an important role in the regulation of NAD+-consuming enzymes, including sirtuins, poly-ADP-ribose polymerases (PARPs), and CD38/157 ectoenzymes.

NAD+ biosynthesis, mediated by nicotinamide phosphoribosyltransferase (NAMPT), and SIRT1, function together to regulate metabolism and circadian rhythm. NAD+ levels decline over time and may be an Achilles’ heel, causing defects in nuclear and mitochondrial functions, and thus contributing to age-associated pathologies, including neurodegenerative disorders. Restoring NAD+ by supplementing with NAD+ intermediates can dramatically ameliorate these age-associated defects. Thus, the combination of sirtuin activation and NAD+ intermediate supplementation may be an effective anti-aging intervention. We have already touched heavily on CR but here’s a brief overview of Calorie Restriction mimetics and enhancers.

Resveratrol activates sirtuins, a powerful family of “information regulator” proteins that inhibit NF-kB, thereby reducing inflammation throughout the body. Resveratrol also prevents inflammatory mast cells from releasing the histamines that trigger asthma and allergic reactions. Resveratrol decreases production of the adhesion molecules that attract inflammatory cells to vascular walls, one of the principal culprits behind atherosclerosis. Adhesion molecules also permit cancer cells to invade tissue and metastasize. Resveratrol’s influence on NF-kB, a critical protein complex that governs response to proinflammatory cytokines, and in turn plays a significant role in free radicals, cholesterol levels, immune function and cancer prevention.
Pterostilbene – found in blueberries, pterostilbene is a polyphenol closely related to resveratrol. It limits NF-kB activity through multiple complementary mechanisms. In vitro, pterostilbene suppresses invasive tumor activity and enhances therapeutic destruction of cancer cells.
Quercetin can protect against chronic inflammatory conditions such as asthma, inflammatory bowel disease, and arthritis is due in part to its capacity for NF-kB inhibition.
Grape seed extract also disrupts cellular inflammation signaling by blocking NF-kB. Its effect on proinflammatory cytokine production in fat cells may even help combat obesity and type 2 diabetes.

These nutraceuticals have been shown to generate many of the same effects in the body as CR without significant dietary modification. They “mimic” CR’s favourable impact on genes associated with the aging process.

Benefits of Fasting, Intermittent Fasting(IF) and Calorie Restriction(CR)

Several labs have conducted tests on rodents and other mammals in regards to examine the effects of CR and IF. In 2006 Christiaan Leeuvenburgh of the University of Florida’s Institute on Ageing showed eating 8 percent less and exercising a little more over a lifespan can reduce or even reverse age-related cell and organ damage in rats. Let’s look at a few more examples.

Changes to the function of cells, genes and hormones

  • during fasting your body initiates important cellular repair processes and charges to hormone levels.
  • Inducement of cellular repair, such as the removal of waste materials from cells, also known as autophagy. Increased autophagy may protect against several diseases including cancer and Alzheimer’s Disease.
  • Gene expression – beneficial changes to longevity and protection against diseases.

Helps Lose Weight and Belly Fat –

  • Forces you to eat fewer meals, lowers your insulin levels, raises growth hormone levels, and increases your metabolic rate by between 3.6 – 14%, helping you burn more calories.
  • Lowers the risk of type 2 diabetes – one study in diabetic rats showed IF protects against kidney damage, one of the severe and common complications of the disease.
  • Reduces oxidative stress and inflammation. Oxidative stress is one of the key players in aging and chronic diseases.

Prevents Heart Diseases –

  • Heart diseases is the world’s number one killer. Good news is fasting can improve risk factors for heart diseases such as blood pressure, total and LDL cholesterol, triglycerides, inflammatory markers and blood sugar levels. However, more studies need to be done in humans before recommendations can be made.

Fasting Can Help Prevent Cancer –

  • There’s beneficial effects on metabolism that may lead to reduced risk of cancer. Although human studies are needed, promising evidence from animals studies indicates fasting may help prevent cancer.

Fasting is Good for the Brain –

  • Fasting increases a hormone called brain-derived neurotrophic factor. BDNF helps protect the brain.

Fasting Helps with Life Extension – the faintest prospect anything extending lifespans is  exciting. Studies in rats have shown fasting extends lifespan just as well as continuous caloric restriction. In one study, rats that fasted every other day lived 83% longer than the control. Although it has not been proven to be as helpful to humans, fasting has become a popular trend amongst the anti-ageing crowd. Given the known benefits to metabolism and a sundry of biomarkers, as well as the numerous similarities between humans and other mammals, it may be safe to conclude fasting will be a viable option for health-conscious longevity enthusiasts.

As mentioned earlier, fasting can deliver excellent results to people who are looking to lose weight  or improve their overall health, but it is not a walk in the park. You need to be strong enough to fight the pangs of hunger. With few exceptions humans love shortcuts, so I have compiled a few natural appetite suppressants that might come in handy when you need to curb the urge.

Almonds are a rich source of antioxidants, vitamin E and magnesium, almonds increases the feeling of fullness and helps with weight management.

Ginger works as stimulant that energizes the body and improves digestion, thereby making you less hungry.

Cayenne Pepper – just half a teaspoon of this fiery goodness can boost your metabolism.

Apples are filled with soluble fiber and pectin, which helps you feel full. It also regulates your glucose and boost your energy level.

Green Tea in moderation suppresses appetite. The major appetite suppressant factor lies behind its effects on norepinephrine(stress hormone)and dopamine (neurotransmitter key to regulating the brain’s rewards and pleasure centres).

Green Leafy Vegetables serve as low calorie appetizers before your meal. Plus, you get a lot of good vitamins and minerals, but always watch what dressings you put on your salads!

High Fibre Fruits and Vegetables are the best for filling you up. These delay the emptying of your stomach and makes you feel full, which helps you control your weight. These fibre foods include oatmeal, lentils, apples, oranges, pears, oat bran, strawberries, nuts, flaxseeds, beans, blueberries, cucumbers and celery.

Exercise helps burn calories, tones muscles, and improves cardiovascular health. Even though it’s a temporary appetite suppressant, some people find exercising makes them find healthier food choices.

Time – Time is an appetite suppressant?. When you eat too fast you end up eating those few extra calories that are not needed. Try waiting before reaching for a second helping. Sit back and enjoy your meals slowly.

Mint is a handy suppressant. Try drinking mint tea if you are trying to cut back on snacking.

Although these are all well-known appetite suppressants, before you consume anything you haven’t before, please consult your doctor.

Keep in mind that when applying any this information to yourself, please be mindful that you still need vitamins and minerals. Fasting is not about starving yourself. For some people, it’s a way of life. Never go to the extremes when you haven’t fasted before. If you suffer from heart disease, autoimmune disorders, cancer or any other ailment linked with inflammation, please, once again, consult your doctor and speak to a nutritionist to put together a healthful regime. Food is still a necessity. Fasting is not something to do everyday!

As promising as it all seems, more human trials are still needed. Fasting isn’t a cure-all, but it appears to assist in cellular repair, weight loss, and in the prevention of . For now, cultivate healthy eating habits, exercise regularly, stay informed on the latest information, and try to lead a stress-free life.

 Works Cited:

Alarcon De La Lastra, Catalina, and Isabel Villegas. “Resveratrol as an anti‐inflammatory and anti‐aging agent: Mechanisms and clinical implications.” Molecular nutrition & food research 49.5 (2005): 405-430.

Bitto, Alessandro, et al. “Transient rapamycin treatment can increase lifespan and healthspan in middle-aged mice.” eLife 5 (2016): e16351.

Carlson, Anton J., and Frederick Hoelzel. “Apparent prolongation of the life span of rats by intermittent fasting.” J Nutr 31 (1946): 363-375.

Folsom, Aaron R., et al. “Prospective study of coronary heart disease incidence in relation to fasting total homocysteine, related genetic polymorphisms, and B vitamins The Atherosclerosis Risk in Communities (ARIC) Study.” Circulation 98.3 (1998): 204-210.

Fresco, P., et al. “New insights on the anticancer properties of dietary polyphenols.” Medicinal research reviews 26.6 (2006): 747-766.

Gallí, Mara, Frédéric Van Gool, and Oberdan Leo. “Sirtuins and inflammation: Friends or foes?.” Biochemical pharmacology 81.5 (2011): 569-576.

Ho KY, Veldhuis JD, Johnson ML, et al. Fasting enhances growth hormone secretion and amplifies the complex rhythms of growth hormone secretion in man. Journal of Clinical Investigation. 1988;81(4):968-975.

Kim, Hyon Jeen, et al. “Modulation of redox-sensitive transcription factors by calorie restriction during aging.” Mechanisms of ageing and development 123.12 (2002): 1589-1595.

Marziali, Carl. “Fasting Weakens Cancer in Mice.” USC News. University of Southern California, 8 Feb. 2012. Web. 10 Sept. 2016.

Safdie, Fernando M., et al. “Fasting and cancer treatment in humans: A case series report.” Aging (Albany NY) 1.12 (2009): 988-1007.

Sinclair, David A., and Lenny Guarente. “Unlocking the secrets of longevity genes.” Scientific American 294.3 (2006): 48-57.

Sohal, Rajindar S., and Richard Weindruch. “Oxidative stress, caloric restriction, and aging.” Science (New York, NY) 273.5271 (1996): 59.

Verdin, Eric. “NAD+ in aging, metabolism, and neurodegeneration.” Science 350.6265 (2015): 1208-1213.

Post Author: Rima Martin

1 thought on “Longevity and the Benefits of Fasting

    David Drones

    (May 16, 2017 - 2:28 pm)

    I’m new to intermittent fasting but am I to understand that “the gene expression profiles of intermittent fasting and calorie restricted are noticeably different” means ideally to do both? As in reduce calories and incorporate intermittent fasting?

Leave a Reply

Your email address will not be published. Required fields are marked *