Have you felt overwhelmed and completely confused searching the internet for the perfect diet or eating pattern that will help you lose weight, improve blood sugar, balance hormones, build muscle, or whatever it is you’d like to achieve? One person says carbs are great. Another says they’re the devil. And both individuals seem to have research studies to back everything they state. Oy vey.
So let’s start looking at some popular eating patterns or fad diets over the next few months and see if there is any merit to them. My goal is to present you with unbiased findings and limitations, so you can decide for yourself if it’s worth a try. Today, I’m focusing on intermittent fasting, which is also known as time-restricted feeding. This eating pattern can be done in a number of ways, and at its core, is an intervention that alternates between periods of eating and periods of fasting. The two most common patterns are:
5:2, where you eat 0-25% of your usual food intake for two days, followed by eating 100% of your usual food intake for five days
eating within a designated window of time, usually 6-10 hours, and fasting for the remaining 14-18 hours (i.e. eat 8am-4pm with a 16-hour fast).
According to animal and human research studies, intermittent fasting is associated with decreased weight, insulin, glucose, blood pressure, cholesterol, inflammation, and appetite, while improving various gene expressions that promote anti-aging and longevity.
While intermittent fasting has a lot of promising benefits, I found that research containing human subjects is limited. And research containing women? Well, now we are really limited in findings. Once I took all of that in consideration, I was left with four studies. Here is the cliff-notes version of what I found: weight loss, fat loss, improved blood sugar regulation (both glucose and insulin), increased HDL cholesterol ("good cholesterol"), decreased inflammation, improved brain pathway development and regeneration, decreased oxidative stress, improved clearance of damaged cells, and increased production of healthy cells. Limitations: small number of participants, loss of lean muscle mass, increased LDL cholesterol ("bad cholesterol"), unknown lifestyle factors, and unknown risks/benefits for individuals with any sort of health condition (except one study looked at individuals with multiple sclerosis).
So, what does that mean for you? Intermittent fasting or time-restricted feeding appears to offer quite a few benefits worth exploring, especially if you want to improve blood sugar regulation and decrease inflammation. However, due to the time-restriction of eating or fasting days, it’s important to make sure you are eating nutrient-dense foods that provide adequate calories and fiber. In other words, please don’t do the junk food version of intermittent fasting. Instead, choose good sources of protein, healthy fats, and lots of colorful vegetables and fruit, because intermittent fasting or not, you’re going to see a lot of health benefits just by eating more healthfully. It’s also important to work with a practitioner that will help you implement intermittent fasting in a way that works with your specific needs and/or health conditions, rather than against them.
I’d like to hear from you, what are your thoughts on intermittent fasting or time-restricted eating? If you've tried it, what benefits or disadvantages did you discover?
If you are curious to try intermittent fasting, I’m more than happy to help you incorporate it into your life in a way that works for you. As always, if you felt this post was helpful and informative, please like it and share it with your friends and family.
With love, Steph
Jamshed, H., Beyl, R. A., Della Manna, D. L., Yang, E. S., Ravussin, E., & Peterson, C. M. (2019). Early time-restricted feeding improves 24-hour glucose levels and affects markers of the circadian clock, aging, and autophagy in humans. Nutrients,11, 1234-1249. doi:10.3390/nu11061234.
Anton, S. D., Lee, S. A., Donahoo, W. T., McLaren, C., Manini, T., Leeuwenburgh, C., & Pahor, M. (2019). The effects of time restricted feeding on overweight, older adults: a pilot study. Nutrients,11, 1500-1508. doi:10.3390/nu11071500.
Fitzgerald, K. C., Vizthum, D., Henry-Barron, B., Schweitzer, A., Cassard, S. D., Kossoff, E., ….& Mowry, E. M. (2018). Effect of intermittent vs daily calorie restriction on changes in weight and patient-reported outcomes in people with multiple sclerosis. Multiple Sclerosis Related Disorders, 23, 33-39. doi: 10.1016/j.msard.2018.05.002.
Wegman, M. P., Guo, M. H., Bennion, D. M., Shankar, M. N., Chrzanowski, S. M., Goldberg, L. A., …& Brantly, M. L. (2015). Practicality of intermittent fasting in humans and its effect on oxidative stress and genes related to aging and metabolism. Rejuvenation Research, 18(2), 162-172. doi: 10.1089/rej.2014.1624.