If doing the same thing over and over and over again and expecting different results is a fruitless endeavor, what about the research on intermittent fasting? About a year ago, I’ve written about some of the less brilliant research on this ever-fashionable diet method. The 300+ studies on intermittent fasting in 2022 offer more of the same.
A few studies, one of which I will speak about shortly, have to see promising, but they had concerning flaws. I also came across intermittent fasting studies from the 1960s and 1970s, confirming that there really is nothing new under the sun when it comes to dieting – and if any of these diets worked, they wouldn’t. not. intermittently fall out of favor. I will attribute to these early studies the merit of the truthful audacity of some of their languages. A 1970 study even used the term “intermittent starvation”. In effect.
But back to the present. Overall, this latest set of studies continues to show that intermittent fasting is no better than good old-fashioned calorie restriction for weight loss and improving health markers like blood sugar. and cholesterol level. Considering that calorie restriction hasn’t been shown to be good for these things either – except perhaps in the short term – that’s not a ringing endorsement for intermittent fasting.
A study, published last spring in the New England Journal of Medicine, compared time-restricted eating — limiting eating to an 8-hour window each day — with daily calorie restriction and found no difference. Since the participants were only followed for 12 months, we do not know if the benefits observed over this period persisted.
These lackluster results echo two prominent studies in recent years, both published in JAMA Internal Medicine. The first trial recruited 100 participants for a year and found no difference in weight or health between alternate-day fasting — eating 25% of caloric needs one day, then 125% the next — and limiting calories to 75% of needs calories each day. The second study of similar size found that time-restricted eating was also no better than eating throughout the day.
Now I want to point out one of the flawed studies from 2022. When the results of this small randomized clinical trial from China, which concluded that intermittent fasting can reverse type 2 diabetes, were published in December, it got a lot of good press from writers who I think haven’t read the whole thing of the study. (It’s behind a paywall.) I’ve read the whole study, and Houston, we have some issues. First, the ethical issues – the researchers recruited participants and completed most of the study before registering it in the clinical trials register. That’s a big no-no, and the study should never have been published for this reason. It also appears that the researchers only recruited people they were confident would be successful. This means that the results cannot reasonably be applied to ordinary people in the real world. Of the 36 participants randomly assigned to the fasting protocol, less than half achieved “remission,” and these were more likely to be people who hadn’t had diabetes for a very long time.
What worries me about the attention to this study is that there is more than one type of diabetes and many people are proselytizing about intermittent fasting. A 2020 paper published in the Journal of the Endocrine Society reported the case of a 58-year-old woman with stable type 1 diabetes – an autoimmune disease in which the body completely stops producing insulin – who began a diet of ketogenic intermittent fasting based on advice from a friend. She ended up in the emergency room with diabetic ketoacidosis. This is when the body does not have enough insulin to allow blood sugar to enter cells for energy. It therefore breaks down fat into fuel, which leads to a dangerous buildup of ketones in the blood. She was lucky to get quick emergency care because she could have died.
Another thing that worries me about the continued popularity of intermittent fasting is what it might mean for older adults. I recently had two relatives in their 60s who started fasting every morning because their doctors recommended it for weight loss. There are so many problems with it, I hardly know where to start.
First, once you’re past your thirties, your body’s default is breaking down muscle rather than repairing it. To maintain and eventually build new muscle, you need to be intentional about engaging in physical activity and eating enough protein. Not only does research show it takes more protein to start building muscle as we agebut the Hourly of this protein counts.
Eat three meals a day with enough protein — about 25 to 30 grams, or 3.5 to 4 ounces — to each, and you give your body three opportunities to build new muscle cells. Skipping a meal, or eating a low protein meal, and you miss one of these opportunities. It doesn’t matter if you end up eating a lot of protein – say an 8 ounce steak or a huge chicken breast – at another meal. Your body can only break down about 4 ounces of that steak or chicken breast in that meal into amino acids that are the building blocks for new muscle cells. The rest will simply be converted into usable energy or stored as fat.. So it’s not about getting enough protein over a 24-hour period, it’s about distributing that protein throughout the day.
The bottom line is that the accumulation of human research does not demonstrate that intermittent fasting is better than calorie restriction for weight loss, and there is no strong evidence that either method produces any loss. long-term weight. Any kind of weight loss from calorie restriction includes muscle loss (yes, even if you also exercise), but intermittent fasting also reduces the chances of eating a protein-rich, muscle-supporting meal. Muscle maintenance is important for healthy aging, and not just because muscle loss increases the risk of falling, which can lead to broken bones. Just a little food for thought.