It’s hard to remember a time when dieting wasn’t a fact of life for so many, but did you know that the concept of dieting for health reasons dates from ancient Greece? Diata was a word used to describe a way of living that would have included a dietary regimen, as well as other daily habits. During the middle ages, “diets” that commonly involved fasts, as well as confinement, were generally advised by physicians. Today, of course, diet is associated with a way of purposeful eating specifically for weight loss. Perhaps the old adage, “everything old is new again,” could apply to the current trend of intermittent fasting to achieve optimal weight. It appears that the ancient Greek physicians’ intuitions about the relationship between fasting and health were actually spot on.
While there are many effective ways to drop pounds, dieting for weight loss takes determination and dedication, as well as commitment to a long-term healthy eating plan combined with an active lifestyle. Many diets fail because slow and incremental weight loss often leaves one feeling “hangry,” or hungry, cranky, deprived and dissatisfied. But, what about an eating plan that can assist weight loss and at the same time improve metabolic health, without hunger? While most are aware that proper weight maintenance supports overall wellbeing and long-term health, how many know that short-term fasting can lead not only to weight loss, but also to an impressive reduction in blood sugar levels.
Of course, food quality is crucial while on an intermittent fasting plan. As with all reduction diets, a healthy whole food eating plan is necessary when the goal is to lose weight and improve health. Done correctly, intermittent fasting should help to manage weight, improve sleep, increase energy levels, elevate mood and improve cognitive performance.
There are several strategies for incorporating intermittent fasting:
- Perhaps the easiest route is to limit food intake to an eight-hour window each day. This requires no calorie restriction; however diet improvements are likely necessary. The strategy takes a two meal a day approach and nothing is eaten after dinner, as nighttime eating is well associated with a higher risk of obesity. Those who already skip breakfast may find this an effortless way to lose weight, as long as healthy foods are consumed during the eating hours. This plan can help with weight loss without leaving one feeling hungry or deprived.
- The 5:2 diet limits caloric intake to 500 calories on two non-consecutive days of the week. On the other days, a healthy diet of 2,000 calories per day for women and 2,500 for men is consumed. This method may be more sustainable for long-term weight management, as long as one can handle the light eating days.
- Some choose the alternate day fasting method, which allows only 500 calories every other day. This is likely too restrictive and unsustainable long-term for most people.
- Basically effortless, but not the most effective for weight loss, spontaneous meal skipping is the least structured plan where meals are skipped from time to time, especially when one is not that hungry.
- Fasting one to two days a week for a 24-hour period, which, for some, may be the most difficult to accomplish. It does appear, however, that longer fasts provide greater health benefits.
- Studies have found that people on fasting plans tend to lose more weight than those who cut daily calories. The drop out rate appears lower for those who fast on some days but eat normally on others, as people find day to day caloric reduction difficult.
As long as one sticks with the plan and doesn’t snack, insulin levels will drop between meals. This stimulates fat cells to release stored glycogen that the body then utilizes for energy, thereby reducing adipose tissue mass. Nutritional stress, in part, results in cellular level repairs, functional optimization and metabolic rejuvenation. Researchers who study intermittent fasting have found good evidence that fasting does encourage weight loss and may also reduce inflammation, as well as lower blood pressure and resting heart rate, benefitting cardiovascular health by reducing cardiovascular risk factors.
Published research of randomized, controlled clinical trials suggests that caloric restriction, such as intermittent fasting, results in energy deprivation that dramatically improves metabolic health, as well as other physiological and molecular markers of health and longevity. Another study found that just changing the timing of meals, eating dinner earlier and extending the overnight fast, significantly benefitted metabolism even in people who didn’t lose weight. While more research is needed, especially for higher-risk individuals, generally healthy but overweight persons should check in with their healthcare practitioner before embarking on any restricted calorie eating plan.
To recap, try the simplest form of intermittent fasting by limiting the eating window to no more than 8 hours, eat a healthy whole food diet, be active throughout the day, and avoid snacking or eating at nighttime.
What is the origin of the Word Diet? https://culinarylore.com/food-history:origin-of-the-word-diet/
Health effects of intermittent fasting: hormesis or harm? A systematic review. https://pdfs.semanticscholar.org/32d3/6a075b700b9115dc904446e3a1d06e5548ba.pdf
Intermittent fasting: Surprising update. https://www.health.harvard.edu/blog/intermittent-fasting-surprising-update-2018062914156