Intermittent fasting is quickly becoming one of the most popular health and fitness trends. People are using it to lose weight, improve their health, and simplify their lifestyles.
It is also difficult to stick to long term, making it one of the most common diets people who come to see us have attempted unsuccessfully in the past.
This article will uncover what this latest approach to nutrition involves and things to consider before attempting to try it out yourself.
What is Intermittent Fasting?
Intermittent fasting (IF) is an eating pattern that cycles between periods of fasting and eating. No foods are restricted, but you are given times when you should and should not eat. Common methods involve daily 16 hour fasts, fasting for 24 hours twice a week, or the 5:2 diet – consume only 500-600 calories on two non consecutive days but eat normally the other five.
The idea is that by reducing your calorie intake, all three methods should cause weight loss as long as you don’t overcompensate by overeating during the eating windows.
There is now a growing body of research suggesting the timing of the fast is key, and can make IF a realistic, sustainable, and effective form of weight loss and diabetes prevention, especially when combined with a healthy diet and active lifestyle.
Intermittent fasting also makes sense on a biological level: simply put, when we eat, food is broken down by enzymes in our gut and ends up as molecules in our bloodstream. Carbohydrates, especially sugars and refined grains (like white flour), are quickly broken down into sugar, which our cells use for energy. If our cells can’t use all the energy, we store it in our fat cells and it becomes…well, fat.
However, sugar can only enter our cells with insulin, a hormone made in the pancreas. Insulin brings sugar into the fat cells and keeps it there.
Between meals, our insulin levels will go down, allowing fat cells to release stored sugar for energy. The idea of intermittent fasting is to allow insulin levels to go down far enough for long enough to burn off fat.
The problem is, intermittent fasting is HARD.
Initial studies were done to compare fasting done every other day with eating less on a daily basis. The results showed both methods worked essentially the same for weight loss – but people tended to struggle with the fasting days (who wouldn’t?!) – so why bother with the fasting?
New research is showing that not all approaches to Intermittent Fasting are the same, and some are just as effective but far more reasonable.
We have evolved to be in sync with our day/night cycle – our circadian rhythm. Our metabolism is adapted to eating in the day, sleeping at night. With this idea in mind, researchers from the University of Alabama conducted a study with a group of obese men with pre-diabetes.
The study found simply changing the timing of meals to eat earlier in the day and extending the overnight “fasting” period caused significantly lower insulin levels, lower blood pressure, decreased appetite, and benefited metabolism.
Is Intermittent Fasting Right for Me?
According to Dr. Deborah Wexler, associate professor at Harvard Medical School and Director of Massachusetts General Hospital Diabetes center: “There is evidence to suggest that the circadian rhythm fasting approach, where meals are restricted to an eight to 10-hour period of the daytime, is effective.” However, above all “use an eating approach that works for you and is sustainable.”
Here’s the deal. There is some good scientific evidence suggesting that circadian rhythm fasting, when combined with a healthy diet and lifestyle, can be a particularly effective approach to weight loss, especially for people at risk for diabetes.
However, there are some red flags and cases where IF should be avoided. These include people with advanced diabetes or who are on medications for diabetes, people with a history of eating disorders like anorexia or bulimia, and pregnant or breastfeeding women should not attempt intermittent fasting unless under the close supervision of a physician who can monitor them.
Should You Give Intermittent Fasting a Try?
Well, it depends.
Before attempting any new approach to your nutrition, the essential first steps are to lay a good foundation of nutrition and health. This includes:
Regularly consuming nutrient dense minimally processed whole foods at meals.
Exercising every day.
Having a healthy relationship with food.
Without these three critical pieces in place, Intermittent Fasting will be almost impossible to stick to.
Intermittent fasting is great for some people, and really hard and discouraging for others. If you are interested in giving it a try, we recommend speaking with your physician, registered dietitian, or certified nutritionist to guide you through the process.
No matter what, here are four ways to use this information to improve your health:
Avoid sugars and refined grains. Instead, eat fruits, vegetables, beans, lentils, whole grains, lean proteins, and healthy fats…a sensible, sustainable approach to nutrition.
Let your body burn fat between meals. As much as possible, avoiding grazing throughout the day. Stay active and build muscle through strength training.
You may consider a simple form of intermittent fasting. Limit the hours of the day when you eat, and for best effect, make it earlier in the day between 7 am to 3 pm, or even 10 am to 6 pm, but aim to avoid eating in the evening before bed
Avoid snacking or eating at nighttime, all the time.
As we always say, the BEST approach to a healthy diet and lifestyle is the one you can stick with long term. If tracking hours when you can and cannot eat is stressful or causes you to overheat on not-so-good for you foods, your best bet is to simply aim for eating balanced meals and snacks throughout the day full of nutrient dense whole foods. In the long run, that will be a much more beneficial approach to your health.