Can intermittent fasting trigger some negative health effects? What are intermittent fasting side effects? How this affect your health?
These are the questions that we will try to answer in this article.
Fans of intermittent fasting (IF) rave about all the purported benefits, yes. But behind all the talk about what type of fasting schedule is right for you or whether you can combine IF with other diets like keto, there’s an often-overlooked fact: IF can still cause side effects or have its negatives…especially if you’re not doing it right.
“It’s important to figure out which style of IF works for you, whether that’s a shorter versus longer fasting window or only doing it so many days per week,” says Alyssa Koens, lead registered dietitian of weight loss coaching company Profile Sanford.
“If you’re consuming too few calories or nutrients during fasting times, you could have side effects.”
But since there aren’t any formal guidelines for how many calories you should be consuming during IF—or for what kinds of foods you should be filling up on during non-fasting hours—it can be hard to hit your IF groove without some bumps in the road first…assuming it’s even the right choice for you at all.
And there are some signs to watch out for that might mean it’s just not the best fit for you and your lifestyle.
Intermittent fasting isn’t risk-free
Before getting into intermittent fasting, everyone should have a conversation with their physician.
That’s especially true if you’re at high risk for health problems or complications—that is, if you’re over 65 and/or have an existing medical condition.
It is also recommended talking to your doctor if you’re on medication since dosing schedules are often built around regular meal times.
Ditto if your job involves handling heavy equipment or other tasks that might endanger yourself or others if you were to experience lightheadedness or the other side effects of low blood sugar.
You should avoid fasting altogether, though, if you have higher caloric needs—that is, if you’re underweight, younger than 18, or pregnant or breastfeeding.
Also, avoid fasting if you have diabetes since fasting could cause your blood sugar to plummet to dangerously low levels.
Read More: Late Night Snacks for Diabetics
You absolutely shouldn’t fast if you’re susceptible to developing an eating disorder. Risk factors include having a family member with an eating disorder, perfectionism, impulsivity and mood instability.
Dietary restriction can cause eating disorders in people with these risk factors, he adds, and studies have associated fasting with a higher risk of bulimia in particular.
Intermittent Fasting Side Effects
1. Being Uncomfortably Full After Eating
Most of us are used to eating several meals a day. This makes it easy to consume enough food without being overly full.
But with a small feeding window, you have to eat one or two big meals. These big meals can leave you feeling uncomfortable and constipated.
Furthermore, eating big meals at night can reduce the quality of sleep.
Most times you’ll be very hungry when the fasting period ends. So you’ll eat a lot of food and also eat again after a few hours before you start fasting again.
With IF, you have to learn to handle big meals and you should be comfortable with your stomach being stretched out for a few hours. Also, note that digesting a big meal can put stress on the body.
2. Obsession With Fasting And Feeding Window
Some IF dieters obsess over when they’ll eat. They go to the extent of counting down hours and minutes to the feeding window.
This leads to an obsession over food and folks start thinking about food all the time. Other dieters stop following IF dieting protocols and extend the fast period to lose weight faster.
Unfortunately, this leads to unhealthy weight loss and regain of weight in the future. These obsessions don’t last long so the dieters eventually go back to old (unhealthy) eating habits.
Surprisingly, some dieters like IF because it reduces the obsession of eating after every few hours. They prefer the simplicity of one or two meals a day.
3. Over-Reliance On Coffee
Many intermittent fasting plans allow dieters to drink coffee to control hunger and stay energized. But drinking coffee regularly can lead to addiction.
And as you may know, drinking caffeine can lead to poor sleeping habits, stress, and anxiety – causing weight gain in return.
Also read: How To Make Gut-Friendly Coffee
4. Hunger And Food Cravings
Hunger and cravings are usually a challenge for anyone trying to lose weight. If you can’t control hunger and curb your cravings, you won’t lose weight.
Some people experience hunger pangs even when they eat six meals a day. So fasting makes their hunger much more intense.
But realize it’s natural to feel hungry at the start of an IF diet and your body may get used to hunger with time.
5. Reduction In Athletic Performance
It’s okay to train moderately when fasting. But doing intense workouts like power-lifting, cross-fit, or high-intensity interval training can hurt you.
Research shows that athletic performance usually diminishes when fasting. In a study, Senegalese researchers tested the athletic performance of runners during Ramadhan and during the non-fasting time.
And they found that the athletic performance of the athletes reduced significantly during the month of Ramadhan.
Other studies also show an increase in fatigue after intense workouts when fasting.
Many people experience heartburn when practicing IF. Sometimes, the heartburn rectifies itself after 5–6 weeks, but if it doesn’t, then you should see a doctor.
The heartburn happens because the body is used to your old eating pattern, so it releases acids at certain times. And when you change the eating pattern, it’ll try to stick to previous eating behaviors.
Also Read: Heartburn and Acid Reflux Natural Remedies
Headaches are a common occurrence during fasting. Most folks complain of mild headaches now and then, while others experience them throughout.
Drinking enough water helps relieve headaches in some cases.
8. Negative Effect On Pregnant Women
Some studies show that fasting during pregnancy does not affect the fetus or the mother. But you may want to avoid IF during pregnancy.
Let hunger dictate what you eat during this period. Don’t starve yourself or the fetus in the name of intermittent fasting.
After all, fasting may not be beneficial during pregnancy. The intermittent fasting side effects on this list can make life harder for you during pregnancy.
9. Frequent Diarrhea
Many IF PR practitioners experience diarrhea after fasting. But how severe it depends on how long the fast was.
Longer fasting duration causes explosive diarrhea. This is caused by high fluid intake – drinking a lot of coffee and water.
10. Brain Fog
Brain fog and feeling sluggish are also common with many IF dieters. But the brain fog usually disappears after some time. Some studies show that long term fasting improves brain function.
11. Negative Effect On Women’s Hormones
Some women who try Intermittent Fasting claim to experience missed periods, metabolic disturbances and early-onset menopause.
Women’s reproductive hormones are highly sensitive to energy intake. So going for long hours without food affects the functionality of these hormones.
Other negative effects include adult acne and obsession over body image.
12. Low Energy
Low energy is one of the biggest concerns for folks who want to try intermittent fasting. And it’s a genuine concern.
Fasting results in low energy and weakness. This can stop you from exercising or staying physically active.
Does Intermittent Fasting Enhance Weight Loss?
I didn’t mention weight loss as one of the benefits of intermittent fasting and here’s why – it’s the total number of calories you consume in a day that determines weight loss, not when you eat.
Intermittent fasting can help reduce the total number of calories you consume in a day. Most intermittent fasting methods give you a small feeding window to eat all your daily calories.
And it’s hard to overeat if you only have a few hours to eat. Subjects in a study were able to reduce their calorie intake by up to 8% when practicing intermittent fasting.
Intermittent fasting helps with weight loss only if you restrict your calorie intake too.
Note that intermittent fasting can help you lose weight only if you maintain a calorie deficit. Besides that, it has no weight loss benefits. So eating one or two meals a day won’t help you lose weight if you overeat.
A group of researchers from the Netherlands conducted a study to find out if intermittent fasting has weight loss benefits. They divided their subjects into two groups.
One group was on a regular diet and another on an IF diet – they all ate the same number of calories and had the same diet composition.
And the researchers found no difference in body fat and lean body mass of the two groups after the study was complete
Conclusion: Intermittent fasting is good for maintaining health and cleaning the body from toxins. If you start practicing you should be aware of these intermittent fasting side effects and it is good to consult with your doctor first.
If it’s not working for you don’t practice intermittent fasting. Try eating smaller meals a day be physically active and you will lose weight.