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Nutritionist weighs in on intermittent fasting

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One type of intermittent fasting is the 5:2, in which a person fasts for two days out of the week. Keri Gans cautions this is still a restrictive, possibly harmful diet.

There have been a lot of fads over the years that claim to help people lose weight. Right now, some of those fads include things like the Paleo Diet, Whole 30 and Keto, and a very popular one right now is intermittent fasting.

Keri Gans, a registered and certified dietician nutritionist, joined “Take Care” to talk about intermittent fasting and the effects of practicing it.

Gans, who is also author of the book “The Small Change Diet,” said there are two popular types of intermittent fasting. The first is the 5:2, where a person eats whatever they want for five days per week and then fasts for the remaining two, eating no more than 500 calories. The second type is when a person eats during a set time throughout the day, usually a period lasting eight hours. Outside of that time period, the person fasts, going possibly 16 hours without food per day.

“It’s the restricting of calories, so basically, when they’re fasting, they’re not eating, and there’s only so many calories that most people will consume in that set eight hours of eating,” Gans explained the latter.

Gans said that intermittent fasting is a type of diet, as it applies restriction to work, but it’s restricting something different from the typical diet.

“It is like a lot of diets in that there’s the word ‘restriction’ there,” Gans said. “It might not be restricting your food choices, but it is restricting the quantity that you eat when you eat.”

As far as health benefits go, Gans cautioned that, though a person who fasts in this way may lose weight, due to the restrictive nature of the diet, it’s very difficult to maintain it long enough to keep the weight off.

“The bottom line is can you keep it up?” Gans said. “That’s what makes a lot of these just another fad diet. … It makes it that an individual cannot continue it, and therefore, they fail, and then, they’re looking for the next fad diet.”

There are some additional drawbacks to this diet, particularly when it comes to possibly introducing some unhealthy eating habits. This is why Gans cautions that somebody who has a history of any eating disorder should not intermittently fast.

“It would not be recommended because of the idea of restricting when you eat and literally fasting,” she said. “So, that’s not necessarily a healthy concept for many people.”

But some have found success, she said. Gans supports a modified version of the daily intermittent fasting, where a person might stop eating after a certain hour of the evening, like 8 p.m., to cut out late-night snacking.

"Some people have been successful, but the question is for how long, and that's the bottom line."

Long term, Gans said intermittent fasting doesn’t pay attention to the quality of the calories consumed, leading to the perpetuation of unhealthy eating habits and a decrease in nutrients.

“If you’re intermittent fasting, but the foods that you’re choosing are not healthy foods, well then, at the end of the day, you’re going to be lacking in certain nutrients that would be important to, let’s say, build your immune system,” Gans said. “So, we need to step away from the actual concept and look at the foods that a person’s actually eating.”

These are all things Gans keeps in mind when advising people about intermittent fasting. If someone approached her wanting to try out the diet, she said the first question is why they want to make their life difficult when healthy eating doesn’t have to be so hard.

“I don’t think that a person has to restrict themselves in order to have a healthy eating … routine,” she said. “I would encourage them to see if we could teach them about portion sizes and how to eat more fruits and vegetables and still eat the foods they love -- because that’s important -- but maybe in a healthier way, maybe not as often, maybe in a smaller serving.”

If a person still insists on trying intermittent fasting, Gans said she is far more comfortable with the daily fasting than the weekly if the person is healthy and isn’t on any medication.

One way some practice the eight-hour fasting is skipping breakfast, and though that’s a relatively small restriction, Gans cautioned that breakfast is important in its own right.

“I’m a huge breakfast fan,” Gans said. “Now, research doesn’t necessarily support -- believe it or not -- those that eat breakfast are thinner. However, I would argue those that eat breakfast are getting certain nutrients they might not get throughout the rest of the day.”

Gans said that a person’s success is often highly dependent on the person’s lifestyle, psychology and personality. And diets are typically not as effective as lifestyle changes.

“Some people have been successful, but the question is for how long, and that’s the bottom line,” she said.

The often failure of diets is why Gans supports lifestyle changes instead, and she said those lifestyle changes have to be tailored for the individual.

“I like to talk about as a lifestyle change, and it’s important for me to get to know the individual and know what their lifestyle is,” she said. “There’s all different factors that can affect somebody’s eating, and it’s important to get to the bottom of that in order to help a person.”

In “The Small Change Diet,” Gans describes these lifestyle changes, advocating for small, habitual changes that people can make to have an impact on their weight. This method helps a person ease into healthier eating without the all-or-nothing approach dieting typically takes, she said.

Small changes can include a variety of things. Gans used the example of a person who doesn’t eat breakfast starting with the goal of eating breakfast every day. That might start with one banana in the morning. Then, as that becomes a habit, add yogurt or whole-grain cereal until the person is eating a well-balanced breakfast every morning. Similarly, a person who doesn’t eat any vegetables may start by eating one serving of vegetables per day.

“Let’s find a way to make it inclusive into what you’re presently doing, get it so it becomes second nature, then move on, then tackle something else,” she said. “Too many diets ask somebody to change their entire lifestyle all at once, and that sets them up for failure.”

Focusing on how to improve rather than what to cut out can encourage the person to keep at it, helping to create a healthier lifestyle to find long-lasting success.

“It’s more about what you should be doing more of and not what you shouldn’t be doing, and if you create some of these better habits, maybe some of the lesser, the habits that aren’t as healthy for you, they start to naturally fall by the wayside,” she said. “We’re focusing on improvement, and then with that, everything falls into place.”