Question of the week
Fasting is increasingly on patients’ radar, but guidance on its risks and benefits isn’t one-size-fits-all. Individual conditions and health needs, such as age, cardiovascular risk, diabetes, or pregnancy, affect who might benefit from practices like intermittent fasting or time-restricted eating.
Helping patients take control of their health through fasting can be challenging for clinicians, who must balance supporting patient goals with ensuring safety. On Healthcasts, our community shared how they counsel patients considering fasting, the safety concerns to watch, and strategies for weighing benefits against individual health risks.
Have you discussed fasting with your patients? Log in or sign up to share how you handled the conversation and view the consensus summary.
Post:
Fasting has gained popularity as a health trend in the past few years with the rise of obesity. The Nobel Prize for medicine in 2016 was given to Ohsumi for demonstrating autophagy with fasting. In 2024, at the American Heart Association Epidemiology and Prevention Conference, they highlighted a research poster that studied an 8-hour time restriction eating and linked it to a 91% higher risk of CV death.
Questions for consult
How do you advise patients on the risks or benefits of fasting?
Comments
Key takeaways about advising patients on the risks and benefits of fasting:
- Fasting guidance must be individualized
Clinicians emphasize that fasting isn’t universally beneficial—health status, cardiovascular risk, age, and past medical history all shape whether it’s appropriate. - Exercise caution with adherence and metabolic risks
Many patients find it difficult to stick with fasting long-term, and some overeat during eating windows, which can slow metabolism. Older adults and patients with diabetes are particularly at risk for dehydration, nutrient deficiencies, and other complications. - Sustainable, supervised approaches are preferred
Most agree that balanced nutrition, exercise, sleep, and stress management provide more reliable long-term benefits than fasting alone. However, if fasting is pursued, a nutritionist's support is recommended.
Family Practice
"When I talk to patients about fasting, I keep the advice simple and personal to their situation. I explain that fasting can have some benefits for certain people, but the research is mixed, and there are also risks, especially for those with health issues like diabetes, pregnancy, or a history of eating disorders. I remind them that healthy eating, exercise, good sleep, and stress control are usually more important for long-term health than fasting alone.
If they still want to try fasting, I help them choose a safe approach, make sure they’re getting enough nutrition, and check in to see how they’re feeling and whether it’s working for them. I am also a strong advocate of intermittent fasting if medically appropriate."
Internal Medicine
"I am not a big fan of fasting as I don't believe most people can adhere to and thus succeed long term. Generally, I am open to patients' weight loss attempts by the method of their choice, as long as it isn't dangerous. Meta-analysis of different weight loss plans has shown that patient adherence is the key. I remind them not to exceed 8 hrs of fasting and not to become dehydrated. I would advise older patients (>70) not to fast."
Endocrinology/Diabetes
"I counsel patients that fasting has pros and cons, and decisions should be personalized based on overall cardiovascular risk."
Family Practice
"I advise very much against it. Firstly, with fasting, one's metabolism can irreversibly slow, a strong recipe for the inability to achieve weight loss long-term. Secondly, not receiving the daily requirement of the major food groups, vitamins, and minerals is likely to be detrimental to health. A low caloric intake spread over the course of each day, combined with aerobic exercise a minimum of five times weekly, will often achieve the desired weight loss goal."
Internal Medicine
"I do not recommend fasting, especially for patients with diabetes. With intermittent fasting, many people, to my observation, tend to overeat during the eating window, which doesn’t benefit them. I usually recommend getting nutritionists or registered dietitians involved for a more supervised personalized plan."
What other risks and benefits should patients keep in mind when thinking about fasting? Leave your suggestion and read other practitioners' comments on the full post on Healthcasts.
