Wed | Feb 19, 2020

Dear Doc | How safe is intermittent fasting?

Published:Sunday | January 19, 2020 | 12:14 AM

Q I started the gym this year, and it was suggested by the gym trainer that I try this new diet, some temporary fasting thing. I have my reservations about these new diet because the last time I tried one – the keto diet – I was a mess. My bowel habit got messed up and my stool was funny. Can I get your medical opinion on this diet?

A The new year always brings with it persons looking for ways to live healthier, and so the various diet trends abound. What was recommended to you is called intermittent fasting and is a diet option you might want to consider.

It actually is not a new concept, and the science behind intermittent fasting has evolved to the point that it can be considered as an option, along with exercise and healthy eating, to improving and maintaining a healthy lifestyle.

How intermittent fasting works is by restricting to a narrow time window during which you can eat your meals. This is usually within a six- to eight-hour interval each day.

When people are fasting, they are slowly burning through the glucose stored in their liver as an energy source. It takes approximately 10 to 12 hours to use up the liver’s energy stores. After these stores are used up, fats are then used for energy.

It is believed that the traditional three-meals-a-day eating pattern does not allow our bodies to utilise our liver’s energy stores and make the switch to fat-burning.

Studies show that intermittent fasting can:

- Stabilise blood-sugar levels.

- Increase resistance to stress.

- Suppress inflammation.

- Decrease blood pressure and cholesterol levels.

- Improve resting heart rate.

- Improve brain health and memory.

Dietician recommended

Considering intermittent fasting as a diet option is also dietician-recommended because it is not completely cutting out any food groups. It is not requiring you to not eat carbs, or fat, but instead just modulating when you are eating healthy food.

It is recommended that for persons who want to try intermittent fasting, they should limit themselves to a 10-hour feeding period five days a week for the first month, then bring the period down to eight and then six hours in subsequent months. The goal would be to achieve a six-hour feeding period seven days a week.

Similar to starting an exercise programme for someone who was previously sedentary, it takes a month or two for them to get in shape while their body adapts to the exercise. It can take between a few weeks to a couple of months for someone to get comfortable with intermittent fasting.

If you typically eat breakfast and tomorrow you don’t eat breakfast, you are going to be hungry and irritable as it gets towards lunchtime. This will be gone after two weeks to a month, if you stick with it.

Another very important practical aspect is not to expect immediate results, either. It can take a few weeks before your body adapts to the point where you will start dropping pounds and experience improved health indicators.

Remember also that fasting does not give you free rein to eat whatever you want, you are still going to have to follow a healthy diet.

There are certain people for whom intermittent fasting is not recommend, such as children, the elderly, and people who already have very low body weight.

Before attempting this and any other diet, you should see your doctor and have a medical done to confirm that you are healthy enough to do so.

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