Try This – Is Intermittent Fasting Dangerous?

For years, longevity and health-minded experts have been promoting intermittent fasting as a way to shed weight, improve our cellular health, and enhance metabolic flexibility. 

But do we really know the long-term effects of this wildly popular practice? 

Intermittent fasting can take on many forms, and one of them is called time-restricted eating, which involves shortening our eating window. For example, the 16:8 method means fasting for 16 hours every day and only eating calories in an eight-hour window. 

Well, this particular form of fasting has come under heat recently since a new study was published featuring initial findings about the potential dangers of this wellness craze. 

Is there any merit to the findings?

Maybe…Maybe not…  

Let’s dive in…

What We Do and Don’t Know 

The American Heart Association released an abstract of their study looking at the impact of time-restricted eating on 20,000 middle-aged adults. They used self-reported data (which can be really unreliable) to gather information on the participants' fasting windows. How many hours a day did they go without eating? 

What they “found” was shocking, especially for those of us who have been practicing some form of intermittent fasting. 

Those who followed the 16:8 method or had a less-than-eight-hour eating window had a 91 percent increased risk of death from cardiovascular disease!

Those with existing cardiovascular disease and an eating window of less than 10 hours a day had a 66 percent increased risk of death from heart attack or stroke. 

How could this be? Isn’t intermittent fasting supposed to reduce our risk of cardiovascular disease? 

Many experts have called attention to the significant limitations of the study, including the self-reported data (it’s hard to be 100 percent truthful about what we eat and when we eat). 

What’s worse, is that only two days of self-reported data were collected. Two day is hardly a reflection of someone's diet! 

Others have called out that we don’t have the full picture because only the non-peer-reviewed abstract has been released, which is true! There are also confounding factors to consider such as the diet quality and other lifestyle habits that could have influenced the health of this particular population. 

The study reads, “Factors that may also play a role in health, outside of daily duration of eating and cause of death, were not included in the analysis.”

These are all major flaws to consider. There’s no way to get a full understanding of someone’s diet and the impact it has on their health by simply asking how long they fast each day. 

One person could be fasting for 16 hours and eating french fries for the remainder of the time. Another person could fast for only 10 hours but eat a well-balanced diet. 

With all that being said, there are some major points to consider before you start intermittent fasting or time-restricted eating. 

Common Challenges with Time-Restricted Eating

I’m not a nutritionist or a physician, but I have talked to hundreds of people about their diets, and there are two major mistakes I notice people make when they try intermittent fasting. 

1. People break their fast with a ton of processed food. Sometimes I’ve seen folks get so excited about the idea of just limiting their calories or skipping certain meals that they don’t stop to think about the quality of the food they’re eating. Breaking a fast with ultra-processed, refined, and carb-heavy food is definitely not the way to go. Not only does this cause a massive blood sugar roller coaster, but it leaves your body starving for real nutrients.
   
   

2. People fail to recognize the importance of our circadian rhythms. Shout-out to Kevin Bass, PhD, for articulating this so well. It is still very common for people to skip breakfast and bulk all their calories together for afternoon and evening meals. What the data shows is that identical meals create different glucose responses depending on the time of day they’re eaten. The same meal eaten for breakfast or earlier in the day creates a lower blood sugar response than when eaten later in the day. 

Now, as mentioned, the study has a lot of problems, but could these items above be two of the reasons that markers of cardiovascular disease increased when people practiced time-restricted eating?

We know that insulin resistance and blood sugar imbalances are leading contributors to metabolic dysfunction including elevated blood pressure and cholesterol. Were these participants not taking advantage of our body’s naturally revved-up metabolism in the morning, leading to imbalances in blood sugar and increases in inflammation?

It’s totally possible! The science is clear that late-night eating or saving the majority of our calories for later in the day is detrimental to our health. 

How I Practice Time-Restricted Eating

After seeing the data on late-night eating and reading so much about the importance of our circadian rhythms, I’ve implemented the 12–14-hour window. This means I fast for 12–14 hours overnight. I also try my best to eat my heaviest meals for breakfast and lunch, and I don’t skip breakfast.

If I were to ever skip a meal, which is really rare, I skip dinner. More likely, I try my best to have a lighter dinner or make sure my dinner is earlier in the evening—at least three or four hours before bed.

Another reason that I, and many of my peers, have cut back on intermittent fasting is that we’ve doubled down on prioritizing lean muscle mass (thanks Dr. Lyon) which means eating enough protein. For me, that’s one gram per ideal body weight, and it’s really hard to get that amount of protein in just two meals a day or a more narrow eating window. 

While there are still a lot of questions about this study that won’t get answered today, there are some things we can know for sure and implement on our road to optimal health. 

Here’s to your health, 

Dhru Purohit