Intermittent Fasting and Health

TODAY WILL NOT ANSWER THAT CHALLENGING QUESTION: What is a healthy diet? Instead, I want to explore the health benefits of intermittent fasting once per week.

Today is not about restricted diets for weight loss; instead, we look at a new study showing how a well-tolerated once weekly fasting approach may improve metabolism and potentially lower chronic disease risks such as diabetes and heart failure.

Intermittent fasting basics

People often use intermittent fasting strategies for weight loss. There are many approaches, including time-restricted feeding and alternate-day fasting. Some studies show intermittent fasting is an effective tool for weight loss. Other studies hint that alternate-day fasting is no better than regular dieting.

For example, a 12–week randomized trial of alternate-day fasting (with 25 percent of the energy consumed on fasting days and free eating on other days) showed a 5.2 kilogram (11.4 pounds) weight loss than a control group.

The University of Illinois at Chicago (USA) study authors offer that alternate-day fasting effectively reduces weight and cardiovascular risk.

On the other hand, a one-year experiment of 100 obese individuals showed that alternate-day fasting did not work better than daily calorie restriction. Participants consumed 25 percent of total energy on fasting days and 125 percent on “feast” days for this trial.

Compared with calorie restriction (75 percent of total energy needs consumed each day) and a no-intervention control group, average weight loss in the two diet groups appeared similar.

What about time-restricted feeding? This form of intermittent fasting has us stop eating by a specific time of day (for example, in the early afternoon). One creates a prolonged period of fasting that carries over into the next day.

Short-term experiments looking at time-restricting fasting suggest that aligning our feeding with circadian rhythms may facilitate weight loss and improve measures of metabolism.

Intermittent fasting, once weekly

Publishing in the European Heart Journal Open, researchers followed 67 subjects, ages 21 to 70 years, for six months. Each subject had at least one symptom of metabolic syndrome (for example, obesity) or type 2 diabetes.

All had elevated LDL (bad) cholesterol levels, but none took diabetes or statin medications.

The participants fasted twice weekly for 24 hours for the first four weeks. Then, they fasted once per week for the next 22 weeks. A control group ate whenever and whatever they wanted.

Study results

When compared with the control subjects, the intermittent fasting group had:

Improvements in markers for insulin resistance and metabolic syndrome. Cholesterol levels did not improve.

More specifically, the fasting participants had higher levels of galectin-3. This substance is an essential protein that plays a part in several cellular processes.

Galectin-3 is associated with inflammatory responses. According to the study principal investigator, Dr. Benjamin Horne, the improvement may lead to a lower risk of diabetes and heart failure.

Dr. Horne adds that “unlike some intermittent fasting plans that are quite restrictive and promise magic weight loss, this approach is not a severe fasting form. The best routine is one that patients can stick to over the long term, and this study shows that even occasionally fasting can have positive health effects.”

Reducing inflammation can improve the cardiovascular environment at a microscopic level.