Intermittent Fasting (IF) is the new diet trend of 2019 and 2020, but I wanted to really break it down and find out how it works and why it might help obesity and health. As we all know 2/3 of adults are obese or overweight, and this is a result of a misconception propagated by medical research on heart disease that fat was the evil food. From 1976 – 1996, we did what they told us and decreased fat from 45% to 35% of all calories. Eating low fats, meant eating higher amounts of carbohydrates which ended up being processed grains and sugars. So, obesity increased from 15% to almost 40% currently. We were also taught that CALORIES were what mattered. However, we all know that calories from a cupcake are very different than those from a carrot. Along with counting calories, came this idea that eating less and exercising more OR calories in and calories out, were what counted. But many Americans and research showed, that this did not ring true. In fact, we exercise the most as Americans, but we also have highest obesity rate. The fact of the matter is that your genetics, brain, and hormones play a significant part in weight NOT calories in and out. We can blame the medical gurus in the 80’s for this current obesity and metabolic disease epidemic.
Now that I’ve debunked your prior thinking on weight, let’s approach a new way to look at weight, championed by Dr. Jason Fung. His ideas promote that insulin activity is integral to weight. Insulin is a hormone made by our pancreas, that helps glucose enters cells. When our cells aren’t sensitive to insulin, it is called insulin resistance. We don’t totally know what causes insulin resistance, but we do see high insulin resistance in people who have diabetes or eat a lot of sugars. Dr. Fung believes that higher insulin levels are guiding your “set-weight” in your brain and upregulate the storage of fat. We know obese patients have a higher fasting insulin and an exaggerated insulin response to food.
The idea behind IF is to lower insulin levels, increase insulin sensitivity, and hopefully impact your set-weight in your brain. By decreasing food intake for a long period, you burn through glycogen in your liver and start burning fat on the body. And by doing this repeatedly, your lower insulin levels help your body lower it’s set weight. Hot off the press, a UCSF study of 116 individuals shows no significant different in weight loss with IF. Yet, we are certainly seeing plenty of anecdotal evidence that it is. Research does show that IF helps with reducing inflammation, blood lipids, blood pressure, oxidative stress, and risk of cancer. In addition, IF improves cellular turnover and repair, growth hormone release, metabolic rate, memory and cognition. Continued examination of IF and IF regimens, will give us more answers on weight loss and its health benefits.
The fact is IF has taken off because of its convenience. Setting a period of time to not eat is based on the individual’s work schedule, circadian rhythms, exercise, family time, medications, and sleep. Stressed out and don’t feel well, take a day off! There are various schedules:
Alternate Day Fasting (ADF)
Modified ADF - 25% of usual intake
5:2 protocol – 25% of calories on two non-consecutive days
Time Restricted Feeding (TRF)- 6-8 hour window of eating.
When starting out, patients need to really understand that there is no guarantee of weight loss, as it will depend on what you are eating when you do eat. It is also contraindicated in breastfeeding and pregnant mothers or anyone with an eating disorder. Anyone who has a chronic disease, on regular medicines, or facing depression and anxiety, should consult their health provider. Talk to a pediatrician for children who are overweight. Success is also dependent on your nutritional status. Fasting will decrease your food intake and therefore the amount of nutrients you get. If you aren’t eating a wide variety of vegetables, consider getting a nutritional analysis like the Nutreval from Genova Diagnostics and seeing a provider for good supplements.
Here are some tips when starting IF.
Really consider what your reasons are for doing IF and are you willing to keep this as a long-term part of your health maintenance?
GO SLOW !
Consider your circadian rhythm and activity
Get support from those around you
Consider electrolyte drinks without sugar (replace salt if needed)
Eliminate snacking first
Then start with either breakfast or dinner and make it work for you and your significant others!
Add exercise slowly, and before you eat.
Reach out to us at firstname.lastname@example.org if you need help!
The information on this site is not intended or implied to be a substitute for professional medical advice, diagnosis, or treatment.
Jason Fung, The Obesity Code.
Sara Gottfried, MD and Kari Hamrick, PhD, RD, “Intermittent Fasting Benefits: Exploring Emerging Research and Clinical Applications”.