Does Time Restricted Eating Cause Cardiovascular Disease?
I am not a doctor, scientist, or expert in anything. This content should not be construed as advice or recommendation, but is intended for entertainment and informational purposes only.
Intermittent fasting and time restricted eating (TRE) are all the rage these days. These lifestyle hacks are supposed to improve our health, help us shed weight, and lead to longer lives.
TRE is essentially squeezing all of your food intake into a restricted time window of usually around 8 hours. The idea is that the body needs autophagy to remove and replace old and damaged cells, but food intake interrupts this process. Supposedly you need at least 14 hours without food for this autophagy process to be completed.
But a recent study presented at the American Heart Association’s Epidemiology and Prevention│Lifestyle and Cardiometabolic Scientific Sessions 2024 claims that TRE leads to a 91% greater risk of dying from cardiovascular disease than someone who does not follow TRE.
So, what’s the deal? Is TRE good for our health, or harmful?
I’ll break down this “study” below, but to summarize, this is a bunch of horseshit, and is a microcosm of what passes for science in the health and nutrition space.
To be sure, I’m not a big fan of intermittent fasting or TRE. Most of the research on these hacks has involved lab animals and worms in very controlled environments that don’t reflect real world conditions.
You can also get many of the same benefits just from eating a diet that allows you to shift from glycolysis to ketosis easily signaling good metabolic health. Intermittent fasting and TRE may be a way to kickstart a person’s metabolism when implementing new lifestyle behaviors for a couple of weeks, and are probably fine to do a few times a month on an ongoing basis.
But I question the long-term effects of consistent fasting and TRE.
It’s difficult to consume enough real food to meet the body’s requirements to function optimally in such a short feeding window. For example, we need around 1 gram of protein per pound of desired body weight to have adequate muscle.
A 150 pound person would need to consume 150 grams of complete protein per day which would be at least 18 ounces of lean steak. Protein is incredibly satiating and most people would find it difficult to eat that much meat in 8 hours or less.
If we fail to consume enough nutrients, our bodies sense famine and shift gears that have impacts on hormone health, muscle development, and more. We’re surviving not thriving when we are nutritionally deprived.
When we’re nutritionally deprived we tend to fall back into old habits, and eat crappy foods because they make us feel good for a brief period of time. Eating adequate real food is much more satiating and helps eliminate unhealthy cravings.
But back to the study in question. Here is the methods section from the study abstract:
Methods: Participants aged at least 20 years who completed two valid 24-hour dietary recalls and reported usual intake in both recalls were included from the National Health and Nutrition Examination Survey in 2003-2018. Mortality status as of December 2019 was obtained through linkage to the National Death Index. An eating occasion required consuming more than 5 kcal of foods or beverages. Eating duration between the last and first eating occasion was calculated for each day. The average duration of two recall days defined typical eating duration which was then categorized as <8, 8-<10, 10-<12, 12-16 (reference group; mean duration in US adults), and >16 hours. Multivariable Cox proportional hazards models were employed to estimate the association of eating duration with all-cause and cause-specific mortality in the overall sample and among adults with cardiovascular disease or cancer. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were derived.
The authors are basing their conclusions on people completing a whopping two 24-hour dietary recalls. These dietary recalls are food surveys that are done from someone’s memory of what they ate the day before and in what time frame.
Do you remember what you ate yesterday and exactly when you ate it?
These dietary recalls are notoriously inaccurate because people tend to have terrible estimating capabilities and recall. Plus, we’re talking about two friggin’ days in this case.
What did these people eat, and more importantly, what do they eat on a consistent basis?
We don’t know.
Did the people who ate in a shorter time window have to do so for reasons that have nothing to do with them practicing TRE on a consistent basis?
We don’t know.
Are the authors controlling for other variables such as existing health conditions and lifestyle factors like smoking, alcohol consumption, drug use, medications, etc?
Doesn’t appear so.
What can this study possibly tell us? Nothing!
This is the type of crap “science” that the American Heart Association, and other medical/health associations, highlight and promote. Many of the AHA recommendations are a great way to induce cardiovascular disease, not prevent it.
But perhaps that’s part of the business model.