Fasting has many health benefits, including regeneration of the immune system, reduced blood sugar, improved insulin sensitivity as well as cellular repair and renewal. However, prolonged water only fasting can be difficult and taxing, both physically and mentally. Diets that mimic the physiological benefits of fasting without the burden of food restriction may be a good alternative.
FMD was developed by Dr. Valter Longo, a professor of gerontology and biological sciences and Director of the Longevity Institute of the University of Southern California (USC). FMD is a low-calorie, low-protein diet that has been shown to cause changes in biochemical markers associated with stress resistance and longevity similar to the outcomes of prolonged water-only fasting.
The FMD, if properly implemented, will put most people into nutritional ketosis, where your body starts burning fat as its primary fuel rather than sugar. For more information about the ketogenic diet, please refer to our previous blog - The Ketogenic Diet - the Basics.
One FMD cycle on this diet usually lasts for three to five days and cycles are fairly infrequent (two to twelve times per year, depending on the conditions being addressed). Between cycles, eating resumes to normal.
Impressive results with FMD in animal studies
FMD is a relatively new intervention and to date most of the research in it has been performed on animals. More research in humans is needed to validate the approach.
One study has even showed that FMD led to regeneration of pancreatic beta cells and insulin secretion in animals with late-stage Type 2 as well as Type 1 diabetes!
FMD has also been shown to have very promising effects on autoimmune disease. In a mouse model of MS, FMD reduced clinical severity in all animals and completely reversed symptoms in 20 per cent of animals.
FMD also has many other benefits, including improving cognitive function and slowing ageing.
The human studies that have been done show impressive results indicating that FMD can have a profound effect on a number of metabolic markers, such as visceral fat, fasting glucose, and insulin-like growth factor (IGF-1).
IGF-1 is an important hormone for cell growth, tissue strengthening, and healing skin. However, too much or too little can have detrimental effects on health and the science is still inconclusive on effects of too high or too low IGF-1. IGF-1 seems to be a major player in accelerated ageing, and one of the effects of the FMD is to slow the ageing process.
In a human trial, fasting was done five days per month for three months. The diet was very low in sugar, but relatively high in complex carbohydrates, low in protein (with no animal products) and high in healthy fats.The trial subjects showed signs of stem cell regeneration and rejuvenation when it followed the FMD followed by a feeding period. It is important to note, that scientists believe that it not just the fasting that is believed to promote cell regeneration, but also the feeding period that follows.
Who should embark on a fast mimicking diet?
It is clear that the FMD has numerous health benefits, however, fasting can potentially make some patients worse, depending on their condition.
The FMD would be suitable for people with weight or metabolic issues including diabetes, fighting chronic infections, those with a weak immune system, neurological issues, cognitive disorders as well as those who are healthy and are simply trying to optimise their health and promote longevity.
People who should avoid the FMD include children and teenagers, pregnant or breastfeeding women, people suffering from hormonal imbalances, anyone suffering from eating disorder or those who have thyroid issues.
The FMD, as studied, is currently available from a company called Prolon as a specific package of ready-made foods and micronutrients. The Prolon plan is designed to be supervised by a medical doctor.
It’s likely that a “homemade” version with similar macronutrient ratios and foods would have the same effects, but note that this has not yet been studied in a clinical setting.
Dr. Valter Longo believes that FMD “switches the clock back a little bit by promoting regeneration and rejuvenation effects” thereby delaying the progression of age-related diseases. Large-scale human clinical trials are being planned to determine whether the FMD should be widely promoted for optimal health. Watch this space!