Nutrition / Food

Should You Sync Your Diet With Your Circadian Rhythm?

Research shows that the time of day that you eat matters.

When most of us think of an optimal diet, we tend to picture healthy foods, moderate portion sizes, and healthy snacks eaten throughout the day.

We also think about healthy fitness programs as well. Aaptiv can help with that!

Most of us tend not to focus on a time frame that we should be fitting in all our meals. Because why would that matter?

Turns out, it actually does. A growing body of research is beginning to suggest that the window of when we enjoy our meals affects our health.

In fact, syncing our diet with our natural circadian rhythm can have some positive health effects.

The Growing Research

In his new book the Circadian Code, Satchin Panda, a professor at the Salk Institute and an expert on circadian rhythms research, argues that eating between an eight- to ten-hour window can help improve people’s metabolic health.

But, this is far from what most people actually do. A typical person, according to Panda, eats within a 15-hour window.

The idea behind this approach, also known as time-restricted feeding, is that our body’s metabolism follows a natural daily rhythm. (This has also been shown to burn fat and increase metabolism).

Different hormones, enzymes, and bacteria seem to be optimized for the morning and afternoon. Just like jet-lag can mess with your body’s natural circadian rhythm and affect your energy levels and your health, so can eating at the wrong times of day, Panda argues.

This approach to eating suggests that we should eat the bulk of our food towards the beginning of the day, and other research supports this. One study out of Israel found that a calorie eaten early in the day is not equal to the same calorie consumed in the evening.

Researchers gave two groups of people the same food items with the same number of calories. However, one group ate a larger percentage of those calories at breakfast.

The other ingested a larger percentage at dinner. They found that the larger breakfast group lost 2.5 times as much weight as the larger dinner group.

They also showed better fasting blood glucose, insulin, and triglycerides, even though the same exact foods and total calories were the consumed by both groups.

What are the benefits?

When we eat at similar times each day, we help our body get into and maintain a rhythm. This can help regulate our hormones, enzymes, and systems.

“For example, if we generally eat every few hours and we eat a well-balanced meal or snack (that has protein, healthy fats, and complex carbs) each day, we will help our body maintain healthy blood sugar balance and help insulin do its job,” says Julie Andrews, MS, RDN, CD.

“If we were to eat at drastically different times or skip meals and go hours without eating, we aren’t necessarily helping our body stay regulated when it comes to hormones and normal processes, etc.”

Eating within a shorter window can also lead to metabolic benefits, such as lower blood pressure and better glucose control.

“We also may lose weight because it’s harder to overeat in an eight-hour window than a 15 hour one, which more closely resembles a typical American diet,” says Lauren Harris-Pincus, MS, RDN.

“Equally important is choosing an eight to ten-hour window that begins and ends earlier in the day, for the reasons mentioned earlier.”

What’s the ideal way to eat, according to our body clock?

Syncing your diet with your body’s natural circadian rhythm requires adjusting your eating routine.

You’ll need to include heavier meals in the morning and have a shorter window in which you consume food. Pincus recommends beginning with a breakfast heavy in protein.

“If possible, I suggest eating a larger lunch and smaller dinner with your last meal, no later than three to four hours before bedtime, if your schedule allows,” she says. So many people say that they are not hungry for breakfast. But if you ask, they are likely eating close to bedtime.”

When eating during an eight-hour window that ends at five or six p.m., there’s a much better chance of waking up ready to eat, she says.

Non-caloric beverages, such as water, seltzer, black coffee, and tea are also allowed during fasting hours. “We want to make sure [that] plenty of fluids are consumed throughout the day and evening hours,” says Pincus.

How is this different than intermittent fasting?

The idea behind time-restricted feeding can seem very similar to intermittent fasting. Although they do have some basic premises in common, they also differ slightly.

“Intermittent fasting, in general, is an eating pattern that cycles through periods of fasting and eating,” says Andrews.

Some intermittent fasting plans can be different, meaning that when you fast and eat are different with each plan. Some fasting plans tell you to fast for an entire day or days, whereas others have you skip certain meals.

“Following the circadian rhythm plan has you fast from the early evening until the morning. [It] tells you to eat only within an eight to ten-hour window,” she says.

Are there downsides to eating this way?

With all this research, it’s hard to imagine why everyone shouldn’t eat this way. But, there are some things to be wary of if you’re thinking of switching to your diet to better align with your circadian rhythm.

Diets of this type can feel restrictive, which may be hard to follow over time, says Andrews. Additionally, it might not be right for you depending on both your physical and mental health.

“Anyone with disordered eating, diabetes, or other medical conditions requiring medication should be very careful about prolonged periods without eating,” says Pincus.

“Plus, if you have a very active lifestyle requiring strenuous exercise or tasks later in the day, it may be more difficult to accomplish without some extra fuel.”

So, what’s the verdict?

With some planning, following a circadian rhythm pattern can be done in a healthy way.

“Start with a larger, well-balanced breakfast. Have a few balanced snacks between meals. Have a normal-sized lunch and a smaller dinner. [This] can certainly be a healthy way of eating,” says Andrews. “But, again, setting any strict rules can feel restrictive. So, we need to be careful about how this plan is set up.”

It’s also important to pay attention to your individual needs, along with the content of the foods you are eating.

“There is much more that goes into a healthy eating and lifestyle plan besides just following a timing pattern,” she says. For now, it might help to eat heavier earlier, and taper off your meals as the day goes on.

In addition to a healthy eating plan, your fitness routines are important as well. Check out the Aaptiv app today for the latest workout classes.

Food Nutrition


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