Fasting for Detoxification?

How safe fasting plans may help support your body’s natural cleansing processes

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Tens of thousands of chemicals have been introduced by industry in the last century, and public concern over the health consequences is high. Particularly shocking are studies indicating that a newborn may have detectable levels of over 200 chemicals in their cord blood. In response to this concern, many detoxification programs promising to remove accumulated chemicals have surfaced, be them drink-based, supplement-based, or some combination of the two.

Of course, this space is highly unregulated. Instead of relying on these potentially unsubstantiated and/or unsafe programs, I advise patients in my clinic to work hard to avoid exposure to toxins in the first place by using glass food containers instead of plastic; switching from canned to frozen foods; and opting for gentle, natural, plant-based mixes that support optimal liver function, should they choose to use them. Many include garlic, broccoli, turmeric, or wheatgrass, for example.

But what about other ways to support your body’s detoxification? Fasting for weight loss or enhanced health has received a lot of attention recently and has considerable scientific support. Beyond the spiritual aspects of fasting, the potential medical benefits have increasingly been substantiated in animal and medical research projects. Fasting protocols may help rejuvenate and regenerate the body, promoting healing in a way that can replace or facilitate detoxification strategies towards optimal health.

The Hype and the Science

The interest in fasting has grown since The Fast Diet was published in England and gained quite a following. This program involves decreasing calories to 500 or 600 calories a day for two days a week and has helped many people lose weight and reverse lifestyle diseases, like adult diabetes.

But there are several types of fasting that have been proposed and studied. While restricting food intake may sound counterproductive, fasting may activate a cell stress response that leads to repair and improved health.

  • Intermittent fasting (IF) means going without food for extended time periods, such as 16 to 48 hours, on a recurring basis.
  • Periodic fasting (PF) describes fasting that lasts from two to as many as 21 or more days. These fasts promote stem cell release that may regenerate tissues and may counteract disease and improve functional outcome in experimental models of a wide range of age-related disorders.
  • The third approach to fasting, time-restricted fasting (TRF) entails limiting daily food intake to eight hours or less and fasting the remaining hours each day.

Fasting Mimicking Diet

Recently, a form of PF known as a fasting mimicking diet (FMD) has caught the public’s attention. FMD resulted from pioneering work on longevity by Dr. Valter Longo and his team at the University of South California Davis School of Gernotology in Los Angeles. It calls for 1,100 calories on the first day and then around 800 on each of the next four days. The nutrients of the foods that are eaten are key; plant-based whole foods like nuts, olives, teas, and soup mixes that are approximately 80 percent fat, 10 percent protein, and 10 percent carbohydrate are recommended. During the five days of restricted calories, exercise and alcohol are out and coffee is limited to zero or one cup a day.

The FMD program was patented by Dr. Longo after years of experimenting with FMD in animal models and showing its benefits on metabolism and lifespan. Dr. Longo’s team then analyzed the effects in a human clinical trial that was published in early 2017. One hundred healthy subjects participated in this study; half of them followed a Prolon FMD five days a month for three months, while the other half ate their usual diet. Improvements were seen in terms of weight loss, fat loss, drops in blood pressure, blood sugar, blood cholesterol, and markers of inflammation in the FMD group.

Even more profound was a drop in a biomarker for cancer growth and an increase in stem cell production, signs of improving health and repair. There are human data suggesting that combining FMD with cancer chemotherapy may lead to improved success and fewer side effects. Animal data suggest that the fasting approach may prompt pancreas cells to rejuvenate and produce insulin, and yield improvements in multiple sclerosis and cognition.

If You’re Considering Fasting

In contrast to the limited data for many detoxification programs marketed in stores and touted, say, on social media, the scientific data for fasting is robust and exciting. While a variety of strategies for fasting may result in weight loss due to calorie restriction, PF and particularly FMD hold promise to rejuvenate and regenerate tissues suffering from aging and disease, and they hold great promise to support a healthy lifestyle for all who qualify.

Make sure to see your doctor before beginning a fasting program to learn if it’s right for you. Not only must a fasting program be deliberately crafted and monitored, but it must be deemed safe for a given individual.

Generally, fasting programs are not recommended for children under age 18; those who are pregnant or nursing; underweight individuals; persons very weakened by a medical condition; or persons with diabetes or advanced cardiac disease, though fasting may also be discouraged because of other health concerns as well.

Of course, you might consider a fasting plan somewhat drastic. For those seeking a less regimented approach, simply not eating for at least 12 hours a day (say, from 8:00 p.m. to 8:00 a.m.) can provide a restorative boost for health.

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