Intermittent Fasting: Is It the Secret to Weight Loss?

I’m not one to follow fads. I rarely try fad diets or trends because they’re usually extremely restrictive, not necessarily healthy, and don't align with what I strive for in terms of personal health. But in my field, I have clients come to me either having tried a fad diet and failed or looking to start one. One of the most popular fads brought up is intermittent fasting. Upon much research, and enough people asking me my opinion, I decided to give it a try this past August. In this post, I’ll go over what intermittent fasting is, its benefits, and my experience trying it for a month.

Now...before we talk about how effective intermittent fasting is for weight loss, we first have to understand what it actually is. By definition, intermittent fasting is an eating pattern that cycles between fasting and eating periods. It doesn’t specify what you eat, but rather when you eat. The goal of intermittent fasting is to put you in a caloric deficit (taking in less calories than you burn) which is needed for weight loss. Intermittent fasting can be done in different ways. Some methods of intermittent fasting include the most popular 16/8 method, the 5:2 diet, and eat-stop-eat. There are other methods of intermittent fasting but I’ll focus on these three. Let’s take a deeper dive into each method:

• 16/8 Method: This is probably the one you hear most about. This method involves fasting anywhere from 12-16 hours and leaving an eating window of 8-12 hours. For some, this may be as simple as skipping breakfast or eating an earlier dinner. For others, it may be a bit more difficult, especially if you usually eat 3 meals a day. An important thing to note is that you can’t just eat anything during your eating window--it should be mostly healthy food choices. I find this to be the most beneficial method for the everyday person. I’ll speak more about my experience with the 16/8 method later in the post.

• 5:2 Method: Now this method may seem a little more easier for some. For 5 days out of the week, you eat normally. And for 2 days out of the week, you restrict your calorie intake to about 500-600 calories. Again, this doesn’t mean you can eat anything on those 5 days. Eating junk food throughout those 5 days will not result in weight loss--this isn’t magic guys. Similar to the 16:8 method, you should keep to general healthy eating habits. This may be considered a more flexible method because you can pick what days to eat “normally” and what days to restrict your calories. You can also eat at any time of day which means no time restriction like in the 16/8 method.

• Eat-Stop-Eat Method: This method may be the hardest to adapt to out of the three. It requires you to fast completely for 1-2 non-consecutive days out of the week. Similar to the previous methods, on days where you eat, you should be mindful of what you eat and don’t overdo it. In a world where nationwide lockdowns, social distancing, and working from home aren’t a thing, you would have to consider the social implications of this method of intermittent fasting--navigating social gatherings, lunches in the office, etc. This method requires a great deal of mental toughness.

Let’s get into the question you’ve been waiting for me to answer...is intermittent fasting effective for weight loss? Yes...sort of. Because I’m a science nerd, I can’t say that, without a doubt, intermittent fasting is 100% effective for weight loss. Most of the research out there only investigates the short term effects of intermittent fasting. Studies also investigate whether intermittent fasting is superior to traditional calorie restrictive diets. A study published in the Nutritional Journal showed that intermittent fasting, combined with calorie restriction on non-fasting days, facilitated weight loss and improved coronary artery disease in obese women. However, another study published by the American Journal of Clinical Nutrition showed that intermittent fasting (the 5:2 method specifically) was not any better than traditional dieting in reducing weight and improving metabolic diseases (such as diabetes, heart disease, etc). So while intermittent fasting can be effective for weight loss, it’s not a miracle diet.

Should women try intermittent fasting? Sure, go for it. But some research shows that intermittent fasting affects women differently than men. There are some studies that show that alternate day fasting (another method of intermittent fasting) worsened blood sugar levels in women but not in men. There are also anecdotal stories where women reported a loss of their periods while doing intermittent fasting. Most medical professionals don’t advise intermittent fasting while pregnant or breastfeeding.

This past August, I tried intermittent fasting for myself. As I mentioned earlier, a lot of my clients have asked about intermittent fasting. So, I hopped on the bandwagon and tried intermittent fasting for a month. I chose to do the 16:8 method because it is the most popular method (and to be completely honest with you, I was not interested in doing a 24hr fast). I set my eating window from 12-8pm daily, knowing that I usually eat later than most and generally don’t have a large breakfast when I do. When I started, I set some goals for myself. During this month of intermittent fasting, I wanted to: 1) control my cravings 2) make healthier food choices 3) understanding hunger vs. thirst cues and 4) develop better sleeping habits. Funny enough, weight loss wasn’t on my list of goals. But wait until the end to find out if it happened.

I’m not going to lie, the first day was tough. Mostly because I was actively thinking about not eating (Pro tip: don’t do that). I started work that day around 8am, which left me 5 hours awake with no food. I knew that I had to develop some type of morning routine that involved taking in a lot of fluids if I was going to succeed with this fast. Over the next couple of days, I developed a routine to help with getting used to fasting in the mornings. First, I would steep about 16oz of tea (no sugar or milk added). This gave me a variety of taste, aside from plain water, which helped curb my craving to eat something. After that, I would continue to drink water until it was time to eat. Throughout the mornings, I would go for water first and assess my hunger afterwards. If I felt fine, I continued to fast. If I was still feeling hungry, I would break my fast with some fruit or yogurt.

As I continued with intermittent fasting throughout the month, I adapted to the morning fast. With my new morning routine in place, I was taking in about a liter of water before 12pm, which helped tremendously with my water intake. Because my first option was always to drink rather than eat, I was able to understand my hunger cues and decide whether I was just craving something just for the sake of eating or if I was actually hungry. There were some days when I broke my fast before 12pm, and I was ok with that because I was listening to my body. When I did break my fast, it was always with fruit which helped me maintain healthy eating habits throughout the day. I also went to sleep earlier on some days to avoid staying up late without being able to eat (win win). And to top it all off, I lost about 5lbs! Disclaimer: I was working out 4 times a week in August so I’m not 100% sure if intermittent fasting was the sole cause of my weight loss.

I can only speak anecdotally, but overall, the 16:8 method of intermittent fasting was a positive experience for me. I did not feel as if I was dieting, but rather practicing self-control and intentional eating habits. Throughout the whole process, I listened to my body and honored its feelings. For anyone who is considering intermittent fasting, I say go for it! But remember, do what works for you. My experience is personal to me and yours to you.

I’ll end off by leaving you with some tips. Don’t go straight for a 2-day fast because you want “quick results.” I promise you, if that’s your motive, you won’t be successful. I always tell my clients to start with a strong foundation and build upon it. The same applies here. Start off fasting for 12 hours and go from there. Be aware of how intermittent fasting is affecting your body. Notice any changes, both positive or negative. If you are pregnant or breastfeeding, or have any other medical conditions, I would advise you to speak with your provider before fasting. If intermittent fasting ends up not working for you, that’s fine. Intermittent fasting isn’t a “one size fits all” type of diet. Just remember to listen to your body--it usually knows best.