If you want to lose weight, watching what you eat may not be enough. According to a new study in the journal Cell Metabolism, you should also watch the clock to limit when you eat. Eat what you want for eight hours during the day, fast for the rest, and see your weight drop and your health improve. Really?
Researchers from the Salk Institute for Biological Studies and the University of California, San Diego conducted the study to find whether obesity and metabolic syndrome – a group of risk factors that occur together and increase an individual’s risk for developing cardiovascular disease, stroke, and type-2 diabetes – result from a high-fat diet or the disruption of metabolic cycles.
In the study, mice were fed a standard diet (13% fat, 29% protein, 58% carbohydrates) or a high-fat diet (61% fat, 18% protein, 21% carbohydrates) with either unrestricted or restricted access to food over a period of 100 days.
The mice who were fed a high-fat diet and restricted to eight hours of food access daily consumed just as many calories as the unrestricted mice, yet they had more energy, used nutrients more efficiently, gained less weight, and were protected from hepatic steatosis (fatty liver) and metabolic disease. In addition, they had reduced inflammation and exhibited improved motor coordination.
On the other hand, the mice fed the high-fat diet with unrestricted access to food became obese and suffered from high cholesterol, high blood sugar, fatty liver disease, and metabolic disease, despite consuming an equivalent number of calories as their time-restricted counterparts.
The results suggest that the health effects caused by poor diet may partially be due to a discrepancy between our eating schedules and our metabolic cycles or “body clocks.” Lead author Satchidananda Panda suggests that our livers, intestines, muscles, and other organs have times where they will work at peak efficiency and times when they rest.
These organ cycles are critical for metabolic processes including glucose production and cholesterol breakdown into bile acids, and they should function at their peak when we eat and rest when we don’t. However, eating frequently throughout the day and evening can disrupt normal metabolic cycles and cause the cycle to adjust continually, causing a sort of metabolic exhaustion.
While the current understanding is that obesity is the result of multiple factors including excessive calorie intake, sedentary lifestyle, excessive consumption of sugar and artificial sweeteners, and increasing portion sizes, researchers believe this study raises questions about the correlation between food intake and the hours during which we eat.
When compared with past generations, more and more of us eat on the go during the day and stay up later in the evenings working, watching television, or engaging in other activities, often with “midnight snacks” at the ready.
States Panda, “We have increased our eating time in the last 40 to 50 years,” and this shift, the authors indicate, may have drastically changed the way our bodies metabolize our food.
The Bottom Line
This certainly is intriguing news. But, I suspect that to curb the obesity epidemic, we’ll need to do more than stop eating during the evening and early morning.
I’ve always thought that most Americans eat too much, too often. We always have something in our mouths – be it coffee, snacks, sodas, chips, etc. – no matter the time of day.
While the idea of eating smaller meals more frequently has been touted as better for us, we seem to have embraced it a bit too enthusiastically and forgotten what “small” is along the way. “Small” would mean about 100 calories of foods high in protein and fiber and low in saturated fat. Good examples would include: an apple with some peanut butter; a handful of nuts and raisins; or some carrots with hummus.
Though it might be easier to stop eating after a certain time instead of going to the gym and getting a workout, we have to remember that lab mice in a controlled setting and humans in the real world – with all its fatty temptations – are very different. It would be irresponsible and potentially dangerous to cite the results of one study as an excuse to eat high-fat foods for eight hours a day, not exercise, and expect to be thinner and in better health.
I think the concept of giving your body a break is a good one, which is why I do a juice fast each Monday. Whether someone does this, chooses “meatless” Mondays, or stops eating after a certain time each day, I don’t think it hurts to cut back on food.
After all, restricting eating hours costs nothing, and it only requires a clock and some willpower. Why not give it a try?
David H. Rahm, M.D. is the founder and medical director of The Wellness Center, a medical clinic located in Long Beach, CA. Dr. Rahm is also president and medical director of VitaMedica. Dr. Rahm is one of a select group of conventional medical doctors who have education and expertise in functional medicine and nutritional science. Over the past 20 years, Dr. Rahm has published articles in the plastic surgery literature and educated physicians about the importance of good peri-operative nutrition.