Are There Any Risks
Intermittent fasting is not safe for some people, including people who are pregnant, children, people at risk for hypoglycemia or people with certain chronic diseases.
If youre at risk for an eating disorder, you shouldnt attempt any sort of fasting diet, advises Taylor. Intermittent fasting has also been known to increase the likelihood of binge eating in some people because of the restriction.
If youre interested in trying intermittent fasting, you should also be aware of some not-so-pretty side effects. It can be associated with irritability, low energy, persistent hunger, temperature sensitivity, and poor work and activity performance.
Ultimately, you should contact your healthcare provider and discuss these options. They know your health better than anyone else and can offer the right guidance on whether or not any of these intermittent fasting options are right for you.
Who Should Not Try Intermittent Fasting
Not everyone should try IF. A few groups who shouldnt: women who are pregnant or trying to become pregnant , those taking diabetes medication , or anyone who takes multiple medications , Kumar says. Also, if you have a history of eating disorders, introducing periods where youre not allowed to eat can put you on a dangerous path toward a relapse.
Know that IF has some side effects. You may be cranky hanger is real during fasting periods because low blood sugar can mess with your mood. You also still need to have a healthy diet when you do eat. One thought is that it would be difficult to make up a calorie deficit if you fasted for two days, but in our society with access to calorie-dense items, you could probably do it, Kumar says. Focus on balanced, nutrient-packed choices, like fruits, vegetables, lean meats, legumes, and whole grains . Expect that for the first couple of weeks you may deal with lower energy, bloating, and cravings until your body adjusts, Shemek says.
Ease Into Your New Eating Plan
While it might be tempting to jump right into your new eating routine , doing so can be difficult and leave you with increased hunger and discomfort, according to Michal Hertz, RD, a dietitian in New York City. Instead, she recommends starting slowly by, say, doing two to three days of IF during the first week and then “gradually increasing week to week.” Taking thing slow isn’t just a great fasting tip, but a great tip for life .
Risk Of Further Vitamin Mineral And Other Micronutrient Deficiencies
Likely the biggest problem with regular fasting is that one aggravates or induces micronutrient deficiencies. Micronutrient deficiencies are very common. Most people, even those that eat healthy, are deficient in various micronutrients or take in suboptimal levels, typically without even knowing it. For example, studies show that about 70 percent of people are not consuming enough magnesium, a very important mineral for health and longevity. Many people are deficient in optimal levels of iodine, B vitamins, iron , omega-3 fatty acids, vitamin D, vitamin K, zinc and so on.
These deficiencies lead to all kinds of health problems, from brain fog and fatigue to an increased risk of cancer, Alzheimers and accelerated aging.
Fasting, which means eating less, can further lead to deficiencies, which in the long term can compromise your health and accelerate aging.
So if you fast, make sure you take supplements. Because even if you eat healthy, you do need supplements.
How To Lose Weight By Fasting: The : 2 Diet
Following the 5:2 diet involves five ‘regular days’ where there is no restriction on food intake followed by two days of eating a maximum of 500-600 calories each day . Research shows that many people find this type of fasting easier to follow, and there is a degree of flexibility as you can choose whichever two days of the week you prefer as your fast days, provided there is at least one day of eating between them.
On both your regular eating and lower calorie days, is important to make sure that your meals are healthy and nutritious. Many proponents of the 5:2 recommend soups for your restricted eating days as studies in the journal Appetite have shown that they may help make you feel fuller for longer.
The main benefit of the 5:2 diet is the reduced calorie intake on fasting days. In one 50-week study that involved 150 participants following the 5:2 diet, researchers found that this method of intermittent fasting was as effective as traditional dieting for weight loss, and another study in the International Journal of Obesity showed the 5:2 diet to be very effective at reducing insulin levels.
One downside is that if the 500-600 calories are consumed throughout the day, as opposed to one sitting, fat loss might be less substantial and take longer than following a frequent 16:8 diet regime.
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What About Other Hormones
Other hormones may also be impacted by fasting. Thyroid hormones, which regulate metabolism and energy, may decrease during extended fasts, according to animal studies.
Some human studies have also shown changes in thyroid hormones. Still, many practitioners question whether this is actually a concern as thyroid hormones appear to return to normal once subjects start eating again. More research specifically on fasting and the thyroid is needed.
Like estrogen, progesterone production can also drop due to alterations in the HPO-axis and GnRH, throwing off overall hormone balance. If you are curious about the signs of hormone imbalance, I’ve written about it extensively here.
Intermittent Fasting And Women
Although we could benefit from more research on this subject, women should consider what we do know about intermittent fasting before deciding to try this eating style.
Is Intermittent Fasting a Good Weight-Loss Diet for Women?
As suggested above, an intermittent fasting diet is likely not going to help women lose weight. Men are likely to benefit from skipping breakfast or restricting their calorie intake for an entire day once or twice a week. These actions can boost metabolism and lead to weight loss. Women, however, are not likely to benefit from the same diet.
Women who want to optimize their body composition, have consistently high energy, and continually improve their workout performance would benefit the most from a constant calorie intake each day. An unchanging flow of high-quality caloriesrather than intermittent fastingis likely to lead to the best weight loss results for women.
Do Women Get Enough Nutrients on Intermittent Fasting Diets?
Intermittent fasting might actually prevent women from getting enough nutrients. By maintaining an unchanging flow of high-quality calories, women can ensure that they are getting enough nutrients to maximize their health. Because of this, women, more than men, might benefit from sticking to the old guideline of eating four to six small meals per day.
What Kind OF Women Should and Shouldn’t Try Intermittent Fasting?
How To Intermittent Fast
Whether you’re a man or woman, there are several different ways to try intermittent fasting. Here are some of the most popular ones:
16:8 fasting : Fast for 16 or 14 hours each day, and then eat within an eight or 10-hour window. For example, this may mean you stop eating at 7 PM and start eating at 11 AM the next day. This is the most popular form of intermittent fasting as you are asleep for the majority of the fast, making it more sustainable, says Ayesta and McKinney.
Alternate-day fasting: This is when you alternate days of regular eating with days of fasting or having just one meal with less than 500 calories. While this is one of the most well-researched strategies for weight loss and metabolic health, Ayesta says it can be too restrictive for some women and requires supervision from a dietitian or nutritionist.
5:2 fasting: This version has you fast for two consecutive days a week, and eat normal meals the other five days. Due to its extreme nature, Ayesta says it should only be adopted under the supervision of a health professional.
One meal a day: Here, you only eat one large meal daily, typically in the evening. However, this method can lead to binging episodes, says Ayesta, and should be implemented with caution especially for those who are physically active.
Keto And Stem Cells When Fasting
When you enjoy a keto feast at the end of a fasted period, you are fertilizing the vast crop of new cells with fatthe healthiest, most potent fuel available.
When you combine IF with keto, youre getting rid of tons of damaged cellsespecially those damaged from the bonding of sugar molecules in the destructive process called glycation. At the same time, your body is erupting with fresh, fat-fueled cells!
Lab tests on mice show fasting to result in major reductions in the incidence of lymphomas and tumors. The mechanism at work here is the decrease in glucose and insulinif youre not eating sugar, your body isnt producing insulin.
Fasting along with keto starves cancer cells that rely on sugar while promoting short-term atrophy and cell death in a wide range of tissues and organs including the liver and kidneys.
This controlled atrophy and cell that occurs during IF triggers a period of cellular growth and proliferation. Replenishing these growing cells is crucial. But, and this is a big BUT, if you eat high carb, and other cancer-causing molecules when feasting at the end of a period of fasting, studies show that you actually increase cancerous activities and pre-cancerous lesions especially in the liver and intestines.
A high-fat low-carb diet is not only the best way to get the greatest health benefits out of IF, its also the best way to protect yourself against the possibility of doing your body harm.
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Pros Of Intermittent Fasting For Women
“There is substantial research to support the therapeutic benefits of fasting,” says Jillian Greaves M.P.H., R.D., L.D.N. Integrative Functional Dietitian at Prevention Pantry Nutrition. “Some potential health benefits include improved cellular health, improved metabolic markers, and weight loss.”Studies show that intermittent fasting leads to weight loss in women, but doesn’t lead to any more weight loss than a calorie deficit overall. However, the structure of IF makes it easier for some to reduce caloric intake.
Intermittent fasting can boost fat burn too. When we eat, blood sugar rises and insulin is released to take glucose to our cells for energy. Extra glucose is stored as fast. If you don’t eat for 10-16 hours, your body will start to use its fat stores for energy.
A study in the New England Journal of Medicine found that in a fasted state, cellular repair occurs, which is linked to increased longevity, reduced risk of cancer, lower inflammation and improved metabolism. However, many of the studies are in animals and more studies in women are needed.
There’s also emerging research that eating in sync with circadian rhythm keeps chronic diseases at bay. In other words, eating during a 6-10 hour window during the day, when it’s light outside, and reducing nighttime eating.
Intermittent Fasting And Menopause
Menopause and the years leading up to it are characterized by significant shifts in your reproductive hormones. But once you are postmenopausal, meaning you haven’t had a period for at least a year, your hormones usually remain relatively stable.
Menopause is also associated with many other changes in a woman’s health, especially metabolic shifts due to declining estrogen.
During menopause, women often notice weight gain, especially around the abdomen. With the drop in estrogen, the risk for heart disease, insulin resistance, and dementia increases because, as you learned earlier, estrogen plays a protective role.
Intermittent fasting may help since many of the benefits of fasting tie closely with menopause-specific health concerns, including blood sugar balance, blood pressure, weight loss, fat burning, and lipid improvements.
As a result, even practitioners who usually don’t recommend IF may consider menopause a better time to try it simply because postmenopausal women have much more stable hormones during this period of their life, so the potential impact on hormone fluctuations is lower.
Unfortunately, there really isn’t any solid evidence specifically examining intermittent fasting during menopause. From my perspective, IF could be beneficial for postmenopausal women, but once again, it really depends on the individual.
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Craving Sweets After Meals
Insulin resistance can often lead to cravings for sugar and processed carbs. Culturally we are conditioned to finish a meal with dessert, however, a nourished body satisfied after a meal shouldnt be craving sweets. If you are craving sweets after meals, especially if you are full, you may be dealing with insulin resistance.
Mood Swings And Irritability
Another common side effect of eating less food is irritability and mood swings. Coupled with headaches and hunger pangs, this can drive some people up the wall. Some people do better with this than others, so its important to listen to your body and track your own tolerance to fasting.
If you experience low blood sugar levels, this may be leading to these anxious feelings and mood swings.
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Why Does This Happen
- A history of low-fat diets. Most vitamins are fat soluble. If youre not eating healthy fats, then youre not able to absorb a lot of the nutrients from the real foods you consume.
- Many of the refined and processed foods weve consumed contain little nutritious value.
- Your gut health becomes problematic after years of following the Standard North American Diet, and you fail to absorb many of the nutrients from real foods when you start to follow a low-carb, healthy fat diet.
- History of following a low nutrient vegetarian or vegan diet.
Intermittent Fasting For Women Over 40
Research shows that around the age of 40, women begin to experience changes in their hormone production. And, since there is a correlation between intermittent fasting and hormone production, its only normal to wonder if there are any differences in the benefits of practicing intermittent fasting in your 40s.
Im now over 40 and can say that I continue to feel that there are benefits of IF and that I do not experience any physical differences between fasting in my 30s and now. If anything, I feel that it has helped me stay in a routine and stick to healthy eating habits.
I want to first note that you should first consult a licensed medical physician before you jump into intermittent fasting. IF isnt for everyone and therefore, its something to discuss with a professional.
The purpose of this post is to give you an overview of IF schedules, not to provide any professional/medical advice.
That said, when I was putting together this post and my Intermittent Fasting Guide for Women, I researched some 30+ clinical trials to see if there is anything that was specific to women in their 40s, 50s, and beyond.
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Fast For 12 Hours A Day
The rules for this diet are simple. A person needs to decide on and adhere to a 12-hour fasting window every day.
According to some researchers, fasting for 1016 hours can cause the body to turn its fat stores into energy, which releases ketones into the bloodstream. This should encourage weight loss.
This type of intermittent fasting plan may be a good option for beginners. This is because the fasting window is relatively small, much of the fasting occurs during sleep, and the person can consume the same number of calories each day.
The easiest way to do the 12-hour fast is to include the period of sleep in the fasting window.
For example, a person could choose to fast between 7 p.m. and 7 a.m. They would need to finish their dinner before 7 p.m. and wait until 7 a.m. to eat breakfast but would be asleep for much of the time in between.
Caloric Restriction Versus Fasting
Caloric restriction means eating less all the time, whereas fasting means eating less, sometimes.
With caloric restriction, instead of consuming, say, 2000 calories per day, one would consume 25 percent or even 30 percent fewer calories per day. Caloric restriction has shown to extend lifespan and reduce the risk of many aging-related diseases .
However, its not easy to continuously eat less, and to do so for years or even the rest of your life. Some people believe you will always feel hungry, but this is also somewhat relative: after a while many people get used to it.
In fact, caloric restriction does not have to be that difficult. A simple way to eat less is just by eating two meals per day. Not only will this save you some money, but a lot of time, too !
While caloric restriction means restricting calories throughout the day, fasting means going without food for specific periods.
Often, the boundaries between caloric restriction and fasting are somewhat blurry. After all, if you fast regularly then youre also likely to restrict calories overall.
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Are There Any Benefits Of Intermittent Fasting For Women
Based on what we know, intermittent fasting probably affects reproductive health if the body sees it as a significant stressor.
Anything that affects your reproductive health affects your overall health and fitness.
Even if you dont plan to have biological kids.
But intermittent fasting protocols vary, with some being much more extreme than others. And factors such as your age, your nutritional status, the length of time you fast, and the other stressors in your lifeincluding exerciseare also likely relevant.
And, as we mentioned in the research update box above, there may be some support for trying intermittent fasting in women who have PCOS.
But for most women, intermittent fasting is probably not the best approach.