Dr. Alethea Fleming, ND

We are all too familiar with the broken refrain that to lose weight we must eat less and exercise more. However, starvation portions and more time on the treadmill doesn’t work. This series examines several simple tweaks that help keep weight off.

Timing is everything

You may have heard of the 5:2 diet popularized in England in 2013 by Dr. Michael Mosley. It is a simple structure of eating your normal diet 5 days of the week, and a calorie restricted one (approximately 500 calories) 2 days of the week. The idea is that by engaging in intermittent, limited fasting you allow your body to take a break from digesting food and instead work on other important things like reducing blood sugar, cholesterol and weight. It’s fairly well supported in the literature and has its share of fans because it’s not a continuous grueling diet – the flexibility is appealing.

However, many people still find this unsustainable so I like to recommend an easier approach. Fast for 12 hours every night. It’s simple, but has the potential to have a profound effect. A Cell Metabolism journal article[i] in 2012 demonstrated that mice fed the same amount of food (in both a high-fat or a high-carb chow) either spread out over 24 hours or restricted to their 12 active waking hours had drastically different results. The mice in the 24-hour access group became obese, increased blood sugar, blood pressure and cholesterol. The mice in the 12-hour access group had none of these problems. More importantly, if flip-flopped the groups reversed the results. The obese mice lost weight, improved insulin sensitivity, dropped cholesterol and even improved leptin sensitivity (leptin is a hormone that decreases appetite). Fasting 12 hours nightly isn’t that much of a stretch for most people and who doesn’t like an easy answer?


If you already regularly fast for 12 hours nightly try restricting eating to 8 hours per day. Example: Have a meal at 10 AM, 2 PM and 6 PM. This way you are still eating three meals daily and not feeling deprived, but you are giving your body more time not digesting. This allows for a variety of responses in the body which are all being studied carefully now including a decrease fat tissue inflammation, improvements in circadian rhythm and increased diversity in the gut microbiome (more on that later in this series).

One last note on food and timing: If you are going to have refined carbohydrates like bread, simply having it at the end of the meal instead of the beginning (think of the proverbial restaurant bread basket) can reduce your insulin response as much as 30%[ii].

Small steps add up, especially ones that aren’t particularly burdensome to try. Tune in next month for the next installment in the series.

Fleming,-Alethea_resizedDr. Alethea Fleming, ND is a passionate advocate for naturopathic geriatric medicine. A 2007 Bastyr University graduate, she also earned a certificate in Gerontology from the University of Washington. Dr. Fleming is the owner and lead physician of the Vital Aging Clinic in Anacortes, Washington where she provides primary care to all adults as well as adjunctive geriatric care. Dr. Fleming is active in multiple community organizations as well as a member of WANP, AANP and OncANP. In her off hours, Dr. Fleming can be found hiking the beautiful trails of Fidalgo Island, spending time with her wonderful husband and son, or with her nose firmly in a good book.


[i] Hatori M, et al. Time-Restricted Feeding without Reducing Caloric Intake Prevents Metabolic Diseases in Mice Fed a High-Fat Diet. Cell Metabolism 17 May 2012

[ii] Shukla A, Iliescu R, Thomas C. Food Order Has a Significant Impact on Postprandial Glucose and Insulin Levels. Diabetes Care 2015 July

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