Intermittent fasting have took the dieting sphere by storm, gaining in popularity over the recent years, sweeping through the increasingly health-conscious world population much like the low-fat diet did in the 50s. As its name implies, this diet involves cycles between periods of fasting and eating, and comes in many forms, the most popular of which include the 16/8 fast, which restricts eating to 8-hour windows, and the Eat Stop Eat, which involves 24-hour fasts once or twice a week.
There is a growing body of research backing the health benefits of intermittent fasting, the most common of which involve weight loss, improved metabolism, mindfulness, and longevity. But the list obviously doesn’t end there, and although some experts have found the research results to be unconvincing in the long run, we’re not here to talk about the nuts and bolts of starting an intermittent fast — we’re here to address the safety of enrolling into one of these fasts in the thick of this coronavirus pandemic.
As our economy has continued to take on a tumble, and restrictions on out-of-home activities are being reinforced by most governments, it may seem like the ideal time to try out this new form of diet. We’re not exposed to the temptations of unhealthy treats we’re so used to having when we’re free to roam outside our homes, plus our diminished physical activity may seem to dampen the perceived difficulty of following through an intermittent fast protocol.
Experts however, have cautioned against it. Alissa Rumsey, a Nutrition Therapist and Certified Intuitive Eating Counselor who has established herself within the field of nutrition and wellness, says that “now is not the time to try fasting, since it may also inadvertently weaken your immune system and leave you feeling worse.”
“In normal times, once the risk of contracting COVID-19 has abated, prolonged fasts can have profound health benefits, but now may not be the ideal time”
Dr. Peter Attia, who also fosters a podcast channel on health and the science of longevity, recently sent out an email guide for the fasting app Zero, advising against multi-day fasts for similar reasons that Rumsey mentioned.
“We’re being abundantly cautious here, but there’s some evidence that a longer fast (2+ days) can cause a cortisol spike which could temporarily dampen your immune system,” he writes. “In normal times, once the risk of contracting COVID-19 has abated, prolonged fasts can have profound health benefits, but now may not be the ideal time.”
When someone transitions from their normal dietary regimen to an intermittent fast, the prolonged fasting spell could cause a rise in one’s cortisol levels. Cortisol is a hormone that helps the body deal with stressful situations, but is also linked to metabolism, blood sugar, memory, and inflammation. In addition to that, excessive cortisol can trigger fat storage and muscle breakdown, which ironically puts the body at higher stress levels.
To quote from an Insider article on an interview with Alissa Rumsey, she says that “at a time like this, when we are already stressed, the last thing we want to do is put more stress on our bodies.”
Besides the surge of cortisol, intermittent fasting — depending on the method and particular individual — can also come with an array of side effects, such as dampened cognitive performance, sleep disruption, and decreased mental alertness, as well as fluctuating blood sugar levels.
These undesirable changes can affect your work performance and productivity, and perhaps even take a toll on your mood and overall wellbeing. Piggybacking off that point, enrolling in an intermittent fasting can also be mentally taxing, especially during times of heightened anxiety. In contrary to our primary assumption, experts suggest that fasting can cause people to obsess on food, exhausting resources for other cognitive or emotional tasks such as working or managing stress in other ways.
People with preexisting eating disorders have also been cautioned against intermittent fasts, as overly-restricting food schedules might induce anxiety towards eating, or fuel a dangerous rebound stint of binge-eating, since calories are not formally restricted in intermittent fasting.
Some advocates of fasting have claimed that some forms of diets can help strengthen the immune system, such as stipulated by this paper from 2014. Valter Longo’s research claims that a 72-hour fast can help reset the immune system by replenishing the immune system with new cells. Although this may be true, there is one inherent flaw with this notion. During the entire 3 days of the fast, your body undergoes a short-term decline in immune function — something I personally think we shouldn’t take chances on.
There are, however, other things we can do to help ourselves and our communities beyond limiting meals. Dr. Bret Scher of the Diet Doctor community suggests we practice social distancing, follow community guidelines, ensure proper hand hygiene, avert from smoking, get good sleep, and take up moderate exercise to stay fit.