A drug that slowed ageing and protected the body from diseases such as cancer would no doubt cause considerable excitement around the world. While there is no such miracle drug, there is a way to trigger these effects in the body without taking any medicine at all — simply by fasting. You probably think this sounds too good to be true. So what’s the evidence?
There are few carefully conducted large-scale clinical trials. This is not surprising given the difficulties of requiring participants to give up eating over several days. The best empirical evidence, therefore, comes from studies on laboratory organisms such as mice, flies or even yeast. These clearly demonstrate that periodic fasting protects living creatures from most diseases and improves overall health.
In particular, fasting provides astounding protection against most cancers. Furthermore, it differentially protects healthy cells but sensitises cancer cells to chemotherapy drugs. A small, randomised pilot study illustrates similar protection in humans.
So how does fasting work? When we are deprived of energy sources the body acts to conserve energy by diminishing cellular proliferation. This occurs through a reduction in various growth factors — specifically insulin-like growth factor-1 (IGF-1), target of rapamycin (TOR) and protein kinase A (PKA). These changes result in cellular protection through reduction of oxidative damage and inflammation. Essentially, fasting is a challenge to the body, which engages stress response pathways to ensure survival.
Much of the research here comes from the laboratory of Dr Valter Longo, with whom I collaborate at the University of Southern California’s School of Gerontology. His lab focuses on the fundamental mechanisms of ageing that are preserved from simple organisms to humans. It has demonstrated that the IGF-1, TOR and PKA growth factors, or pathways, are critical for promoting ageing in model laboratory organisms and humans. Therefore, their elevation accelerates ageing processes. In fact, low levels of IGF-1 are associated with the longest-living human populations. (These pathways, just to recap, are reduced by fasting.)
They are also associated with disease. High levels of IGF-1 are associated with cancer. Reduced IGF-1 levels are associated with lower incidence of cancer, improved stress resistance, reduced insulin levels and improved insulin sensitivity.
Another surprising effect of fasting is higher energy levels. When hungry, the body is programmed to seek nourishment with increased activity. When we are satiated, in contrast, the body is sedentary.
Unfortunately, fasting is not easy. And it isn’t safe for extended periods of time. This is where the Fasting Mimicking and Enhancing Diet (FMED) comes in: a meal programme that allows you to eat but tricks the body into acting like it is fasting.
The first commercially available programme, which I helped to develop, is called ProLon. It consists of soups, bars, snacks and drinks that contain all the nutrients you need for five days. All the ingredients are plant-based and provide between 1,150 and 800 calories a day.
Preclinical studies show that ProLon inhibits the activity of the major pro-ageing genes including those in the IGF-1, TOR and PKA pathways and, in turn, causes two major changes: 1) the entry of many cells and tissues into a shielded mode which involves the activation of protective as well as repair enzymes; 2) the destruction of damaged intra-cellular organelles and cells followed by the activation of stem cells and the regeneration and rejuvenation of a wide range of cells and tissues.
A randomised clinical trial showed the diet had long-lasting effects in reducing body weight and abdominal fat and maintaining lean body mass. Three cycles of ProLon promoted healthy levels of blood glucose, insulin and C-reactive protein (CRP, a marker of inflammation). Furthermore, stem cells and regenerative markers were elevated. The diet seems to re-programme the body into a regenerating, rejuvenated and resilient mode.
In oncology clinics across Europe and the United States, another such meal programme, Chemolieve, is being tested in cancer patients undergoing chemotherapy. Preliminary results suggest that patients who consume Chemolieve prior to and on the day of receiving chemotherapy treatment experience significantly less chemotherapy-induced side effects.
Given the expansive, system-wide effects of these fasting diets, I believe they will have profound implications for numerous diseases, including diabetes, multiple sclerosis, arthritis, Crohn’s and Alzheimer’s, and change our whole approach to healthy living.
Dr Todd Morgan is research professor at the School of Gerontology, University of Southern California, and Chief Scientific Officer at L-Nutra