Modern Fasting Misconceptions
I got interested in the power and potency of lifestyle medicine in my early 20s; for me, a regular practice of yoga asana and the adoption of a vegetarian diet healed my optical migraines and put my childhood lactose intolerance into remission. Therapeutic elements of lifestyle feature prominently in each plan of care I craft for my patients.
So I've watched with great interest as fasting - particularly different forms of intermittent fasting, like time restricted feeding - has exploded in popularity. If you scroll through social media (which I do not recommend for just about anyone basically ever), you'll find yourself fed countless "influencers" through whatever algorithm promoting various fasting protocols as the "ultimate solution" for everything from weight loss to longevity.
But as with many health trends, the reality is much more nuanced than the headlines suggest.
Long before intermittent fasting became the term du jour, ancient whole-person medicine and healing traditions, including Ayurveda, recognized the impact of fasting and meal timing on health. In the Ayurvedic system, we have long understood that digestion (agni) operates on natural rhythms aligned with the sun's movement. Modern chronobiology and circadian rhythms research continuously validates these traditional insights about circadian rhythms and metabolic health.
And we have similarly long understood that various forms of fasting can be potent tools when deployed for the right individuals under the right conditions. Although it is a fairly intensive example that is not the right fit for everyone, look no further than Dr. Alan Goldhamer's TrueNorth water fasting approach to get a sense of just one of the many clinically-validated approaches to fasting out there.
As someone with a background in epidemiology, I approach health trends with a critical eye toward the evidence. The research on fasting is nuanced; it is sometimes promising, at other times disappointing, and clearly calls for individualized application. For example, while some of studies on time-restricted feeding suggest benefits for metabolic health, insulin sensitivity, and cellular repair processes, these findings come with important caveats that often get lost in popular media.
Let's break down some common myths:
Myth 1: Everyone Should Fast
One of the most problematic aspects of the current fasting trend is the assumption that it's beneficial for everyone. The evidence out there suggests that this is not the case. And in my practice, I've personally seen how this one-size-fits-all approach can be harmful. Your individual constitution (what Ayurveda refers to as prakrti) and the nature of your current health condition plays a crucial role in determining whether and how fasting might benefit you.
For instance, those with a vata-dominant constitution often benefit from short, periodic warm-water fasts, but they may also benefit from a 10-or-so hour time-restricted circadian feeding schedule or from a few days of kitchari or congee-only fasts around periods of transition, such as when the seasons change or around the full moon. Pushing those folks into extended fasting periods can lead to unsafe weight loss on what may be an already thin frame; it may bring on or exacerbate anxiety and sleep issues; and it may also cause digestive and bowel regularity problems among other possible complications.
Myth 2: Longer Fasts Are Always Better
In general, I've observed a concerning trend toward extreme fasting protocols - for example, some out there promote extended time-restricted fasting periods of 20+ hours on a consistent basis. Although this may be effective for short stretches of time for a minority of people in a minority of situation, research suggests that many of the benefits of fasting can be achieved with more moderated approaches. More importantly, longer isn't necessarily better – it's about finding the rhythm that supports your body's natural healing processes without creating additional stress.
When more intensive fasting is appropriate, it should always be done under competent medical supervision. Make sure to discuss with your physician and determine what is right for you!
Myth 3: Fasting Is Just About Weight Loss
While fasting can support healthy weight management, viewing it solely through the lens of weight loss misses its deeper potential for health promotion. In Ayurveda, we understand that periodic fasting, when done appropriately, can support the body's natural detoxification processes and promote cellular renewal – what modern science now calls autophagy.
If you are curious about how our Ayurvedic, integrative health approach - which may include fasting of some kind - can support your health (or the health of a loved one), you can book a cost-free, 15-minute Consultation.
The Missing Pieces in the Fasting Conversation
What often gets overlooked in discussions about fasting are other crucial factors that heavily influence its effectiveness and safety:
Quality of Food - The quality and composition of meals during eating windows matter tremendously. Breaking a fast with processed foods or inappropriate combinations can negate many of the potential benefits. In fact, in some cases, the most valuable aspect of exploring fasting isn't the fasting itself, but the awareness it brings to our relationship with food. In Ayurveda, we emphasize mindful eating practices that naturally create healthy gaps between meals without the need for persistent strict fasting protocols.
Stress Levels - Fasting is a hormetic stressor, meaning it can be beneficial in the right dose but harmful when excessive. If you're already dealing with high stress levels, adding the stress of fasting could do more harm than good.
Sleep Patterns - Your fasting schedule should support - not disrupt - your natural sleep-wake cycle. Late-night eating or extremely early morning fasting can disturb these crucial rhythms.
Individual Variation - Factors like age, activity level, hormonal status, underlying health conditions, and (of course) your doshic constitution all influence how your body responds to fasting.
In my practice at The Buddha's Medicine, I advocate for a more nuanced approach to fasting. Here's what that tends to look like:
We begin by understanding your constitutional type and your current state of health and balance/imbalance;
We consider existing or easily available natural daily fasting periods that align with circadian rhythms;
We focus on the quality and content of meals in whatever capacity they fit into the fasting plan;
We closely monitor how your body responds;
And we adjust the approach based on factor like the season, life circumstances, and how you feel.
It's crucial to note that fasting isn't appropriate for everyone! Contraindications include those who are pregnant, those with a history of eating disorders, particular medical conditions, and the use of specific medications.
If you're interested in exploring intermittent fasting, I encourage you to:
Start slowly and observe your body's responses;
Work with a qualified healthcare provider who understands both the scientific and traditional perspectives;
Remember that fasting is just one tool in the broader toolkit of health practices;
And stay flexible and adjust your approach based on your body's needs.
The Bottom Line
While intermittent fasting can be a powerful tool for health when properly implemented, it's not a magic silver bullet. The key lies in understanding your individual constitution, current state of health, and life circumstances. Rather than following trending fasting protocols, focus on developing a sustainable rhythm that supports your body's natural healing capabilities.
Remember, the wisdom of both ancient healing traditions and modern science points us toward balance, not extremes. Your journey with fasting, if you choose to explore it, should be one that enhances your vitality rather than depleting it.
If you are curious about how our Ayurvedic, integrative health approach can support your health (or the health of a loved one), you can book a cost-free, 15-minute Consultation.
Dr. Matt Van Auken, MD, MPH
Dr. Matt is an Ayurveda-trained, triple board-certified physician.