Ahhh, the internet. Full of fast facts, quick stories, and the latest news every 15-30 minutes. Which means we see stories/news that makes us question or gasp without really knowing all the details.
Before we dive into this recent study, let’s first talk about what intermittent fasting is. I’m sure you’ve heard about it from Jenny in HR or Todd in Accounting—they do intermittent fasting and feel SO much better.
Intermittent fasting (IF) is when you eating only during a window of time every day and then you fast (only drink water) during the rest of that time. There are many ways to do this, but the most popular are:
- Alternate-day fasting: Eat a normal diet one day and either completely fast or have one small meal (less than 500 calories) the next day.
- 5:2 fasting: Eat a normal diet five days a week and fast two days a week.
- Daily time-restricted fasting: Eat normally but only within an eight-hour window each day. For example, skip breakfast but eat lunch around noon and dinner by 8 p.m.
There’s been research done on IF for a long time and most has shown positive results in terms of managing weight, preventing (and even reversing) some forms of disease, and allowing the body to better burn fat.
Other benefits found include improved thinking and memory, improved blood pressure and resting heart rates, the ability to physically perform better in terms of endurance, the prevention of obesity and Type 2 diabetes, and even reduced tissue damage.
However, IF isn’t safe for everyone. If you’re under 18 years old, pregnant, currently have diabetes of insulin issues, and/or have other metabolic conditions, IF isn’t the best way to try to control your health.
Okay, so, there was a study done and released within the last few weeks that got everyone up in arms about IF because it stated that “8-hour time-restricted eating linked to a 91% higher risk of cardiovascular death.”
The key findings were that of the 20,000 adults in the study, those who followed an 8-hour time-restricted eating schedule had a 91% higher risk of death from cardiovascular disease; those with heart disease or cancer also had an increased risk of cardiovascular death; and compared to other eating schedules, limiting food intake to less than 8 hours a day didn’t associate with living longer.
Should you be worried? No, not right now. Here’s why.
The study was technically unpublished data from an observational study, which means that it was NOT peer-reviewed, which means that other researchers, professionals, doctors, etc. in that field did NOT get a chance to see these results and try to test them/prove them right or wrong. That’s problem #1.
The researchers used data from the National Health and Nutrition Examination Survey (NHANES) collected between 2003 and 2018 from more than 20,000 people in the U.S. and followed mortality outcomes, grouping people by average eating duration. Which brings in problem #2: These people used food frequency questionnaires and those are considered unreliable data because they are frequently affected by recall bias thanks to the time and energy it takes to fill them out.
Problem #3 is that this study was done under the assumption that completing two food recall surveys was sufficient data to represent those participants’ normal eating patterns for the next 8 years!
Problem #4 is that there were actually NO significant differences in all-cause mortality, which is the most important metric. This is where they are claiming that the time-restricted eating group had the 91% increase in cardiovascular death risk.
Which brings us to problem #5 of this study: There were SIGNIFICANT differences in the group sizes, other lifestyle habits, and comorbidities… Which means you weren’t comparing apples to apples or even apples to oranges.
A lot of popular, accredited professionals have been speaking out about their frustration behind this study, and the one I used the most (and love to follow in general) is Dr. Peter Attia. So if you’re looking for REAL information about medical dos, don’ts, and facts, follow him. Not what’s randomly published and thrown on People.com’s Instagram (which is where I saw the news first).
If you’re interested in learning more about IF and if it’s right for you, reach out and I can ask you a few questions to help you get started: kelsey@thrivewellmi.com
