Intermittent Fasting (IF) and Time Restricted Eating (TRE) are here to stay.
And for good reasons:
Intermittent fasting is a way to get the benefits of a regular calorie reduced diet without restricting what you eat, just when you eat it.
Intermittent fasting reduces both weight and fat, and can improve blood sugar and blood lipids. It has been shown to reduce blood pressure and some markers of inflammation. Many animal studies show improvements in brain health too.
While these benefits of IF are similar to those with calorie reduced diets, IF has some key advantages including being easier for some people to stick with and it might help people eat more intentionally.
There is also evidence that IF preferentially reduces fat while preserving muscle and may help our bodies become more “metabolically flexible.”
More research is needed to really understand long-term benefits of IF on the body and brain, as well as which IF approach is optimal for different people and different health goals.
IF is one way that women in menopause can manage their hormonal weight gain. Just remember, the studies show that women often do better on a relatively short IF schedule (like 12 hours is enough to get benefits!).
So no reason not to start.
I like to make myself butter teas and Bulletproof type coffees when I am not quite into fasting.
They help me to get closer to a fasted state. Using foods they consist of mainly fibre, water and fat (the types of foods that would be on a keto diet) is sometimes called being on a fasting-mimicking diet.
We can explore that idea in future posts.
As promised, the science:
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Antoni, R., Johnston, K.L., Collins, A.L. & Robertson, M.D. (2016). Investigation into the acute effects of total and partial energy restriction on postprandial metabolism among overweight/obese participants. Br J Nutr, 115(6), 951-9. doi: 10.1017/S0007114515005346.
Brandhorst, S., Choi, I. Y., Wei, M., Cheng, C. W., Sedrakyan, S., Navarrete, G., … Longo, V. D. (2015). A periodic diet that mimics fasting promotes multi-system regeneration, enhanced cognitive performance and healthspan. Cell Metabolism, 22(1), 86–99. http://doi.org/10.1016/j.cmet.2015.05.012
Carter, S., Clifton, P.M. & Keogh, J.B. (2016). The effects of intermittent compared to continuous energy restriction on glycaemic control in type 2 diabetes; a pragmatic pilot trial. Diabetes Res Clin Pract, 122, 106-112. doi: 10.1016/j.diabres.2016.10.010.
Clifton, P. (2017). Assessing the evidence for weight loss strategies in people with and without type 2 diabetes. World Journal of Diabetes, 8(10), 440–454. http://doi.org/10.4239/wjd.v8.i10.440
Fontana, L., & Partridge, L. (2015). Promoting Health and Longevity through Diet: from Model Organisms to Humans. Cell, 161(1), 106–118. http://doi.org/10.1016/j.cell.2015.02.020
Harvie, M., & Howell, A. (2017). Potential Benefits and Harms of Intermittent Energy Restriction and Intermittent Fasting Amongst Obese, Overweight and Normal Weight Subjects—A Narrative Review of Human and Animal Evidence. Behavioral Sciences, 7(1), 4. http://doi.org/10.3390/bs7010004
Headland, M., Clifton, P. M., Carter, S., & Keogh, J. B. (2016). Weight-Loss Outcomes: A Systematic Review and Meta-Analysis of Intermittent Energy Restriction Trials Lasting a Minimum of 6 Months. Nutrients, 8(6), 354. http://doi.org/10.3390/nu8060354
Horne, B.D., Muhlestein, J.B., Lappé, D.L., May, H.T., Carlquist, J.F., Galenko, O., Brunisholz, K.D. & Anderson, J.L. (2013). Randomized cross-over trial of short-term water-only fasting: metabolic and cardiovascular consequences. Nutr Metab Cardiovasc Dis, 23, 1050–7.
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Hussin, N.M., Shahar, S., Teng, N.I.M.F., Ngah, W.Z.W. & Das, S.K. Efficacy of fasting and calorie restriction (FCR) on mood and depression among ageing men. J Nutr Health Aging, 17, 674–80.
Keogh, J.B., Pedersen, E., Petersen, K.S. & Clifton, P.M. (2014). Effects of intermittent compared to continuous energy restriction on short-term weight loss and long-term weight loss maintenance. Clin Obes, 4(3), 150-6. doi: 10.1111/cob.12052.
Li, L., Wang, Z., & Zuo, Z. (2013). Chronic Intermittent Fasting Improves Cognitive Functions and Brain Structures in Mice. PLoS ONE, 8(6), e66069. http://doi.org/10.1371/journal.pone.0066069
Mattson, M. P., Moehl, K., Ghena, N., Schmaedick, M., & Cheng, A. (2018). Intermittent metabolic switching, neuroplasticity and brain health. Nature Reviews. Neuroscience, 19(2), 63–80. http://doi.org/10.1038/nrn.2017.156
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St-Onge, M.P., Ard, J., Baskin, M.L., Chiuve, S.E., Johnson, H.M., Kris-Etherton, P. & Varady, K.; American Heart Association Obesity Committee of the Council on Lifestyle and Cardiometabolic Health; Council on Cardiovascular Disease in the Young; Council on Clinical Cardiology; and Stroke Council. (2017). Meal Timing and Frequency: Implications for Cardiovascular Disease Prevention: A Scientific Statement From the American Heart Association. Circulation,135(9), e96-e121. doi: 10.1161/CIR.0000000000000476.
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