Monthly 5-Day 'Fast' Supposedly Helps Healthy Humans to Keep Aging, Cancer, Diabetes & Heart Disease in Check

Even on the five fasting days per month your plate doesn't have to be completely empty. Real foods, however, weren't served in this trial.

An international consortium of scientists has recently published an intriguing study about the effects of a "fasting-mimicking diet" on markers/risk factors for aging, diabetes, cancer, and cardiovascular disease (Wei 2017). The study builds on the ever-increasing evidence that calorie restriction or changes in dietary composition can enhance healthy aging.

Now, as effective and healthy as it may be, fasting is not exactly what the average pre-diabetic (of whom the study at hand shows that he would benefit most) wants to do and/or what he or she can adhere to in the long run.
To test whether it may not even be necessary to fast for weeks and months, Min Wei et al. conducted a randomized clinical trial with 100 generally healthy participants. With a cross-over after 50% of the study period of three months, the study ensured that all subjects were fed the fasting-mimicking diet (FMD) group for 3 months. Aside from being low in calories and protein -

• day 1: ~4600 kJ = 1100kcal | 11% protein, 46% fat, and 43% carbohydrate 
• day 2-5: ~3000 kJ = 717kcal | 9% protein, 44% fat, and 47% carbohydrate

- the diet that was consumed for 5 consecutive days per months for three months (with a lower kcal-deficit on day 1 vs. 2-5 that's supposed to make it easier to get into the fast), each, was plant-based diet, and designed to attain fasting-like effects on the serum levels of IGF-1, IGFBP-1, glucose, and ketone bodies.

Figure 1: Overview of the study design (left) and post hoc comparisons for changes in risk factors for age-related diseases and conditions by baseline subgroups (right | Wei 2017).

To compensate for the lack of macro and micronutrients the scientists used ready-made food products from USC and L-Nutra (www.prolonfmd.com): vegetable-based soups, energy bars, energy drinks, chip snacks, tea, and a supplement providing high levels (25% of the RDA per serving for most ingredients) of minerals, vitamins, and essential fatty acids were on the subjects' daily menu.

Figure 2: Overview of changes in several markers of metabolic and overall health (Wei 2017).

As you can see in the table on the right-hand side of Figure 1 and the series of graphs in Figure 2, fasting for only 5 out 30 days of a months and a total of 15 days in 3 months yielded quite impressive effects in all (Figure 2) and even greater effects in those subjects with lower metabolic health (see Figure 1, right) - a statistical significance between the improvements in those with the worst and best risk factors in Figure 2 was yet observed only for glucose and IGF-1.
References:

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