Should You Try Intermittent Fasting When Youre On The Keto Diet
Keto and intermittent fasting can be combined for quick weight loss results, but is it safe or healthy? A nutritionist weighs in.
Both intermittent fasting and ketogenic diet are popular eating approaches, but some have suggested taking things a step further by combining the two. So is there any evidence that this works, or, more importantly, is it a healthy approach to weight loss?
Before You Try Intermittent Fasting
If you want to give intermittent fasting a try, make sure to discuss it with your doctor first, says Dr. Rimm. Skipping meals and severely limiting calories can be dangerous for people with certain conditions, such as diabetes. Some people who take medications for blood pressure or heart disease also may be more prone to imbalances of sodium, potassium, and other minerals during longer-than-normal periods of fasting.
What Breaks An Intermittent Fast
If youre new to intermittent fasting, you may have a lot of questions about what to do while fasting1. Does coffee break a fast? What about diet soda, or tea? Can I eat a banana? Or a handful of almonds? What if Im really, really hungry? Read on to discover what really breaks a fast, and how to curb hunger while intermittent fasting for greater success.
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Intermittent Fasting And Metabolism
Surprisingly, research suggests that the effect of intermittent fasting has the same or less negative effects on metabolism compared to traditional dieting. The reason why many think intermittent fasting improves metabolism is due to less loss of lean body mass and greater fat burning. It’s impossible to lose weight without losing a little lean body mass, but research suggests that a lower percentage of lean body mass is lost when losing weight with intermittent fasting than with traditional dieting. Preserving more lean body mass means the body’s calorie-burning slows less. At the same time, short fasting periods cause the body to tap into fat stores and burn a greater percentage of fat mass for energy.
What You Need To Know
If you eat more than you normally would during the five days to compensate for the lost calories on fasting days, you might not lose weight. And if you overeat high-calorie, high-sugar, or overly processed foods on those days, you may even gain weight.
On fasting days, experiment with timing to see what works best for your brain and body. Some people function best with a small breakfast, while others prefer to wait as long as possible to eat their first meal. You should aim to consume about 25% of your normal calorie intake.
Since you have a limited number of calories to work with on your fasting days, try to spread them out as much as possible. For example, if you’re trying to keep your fasting day to 500 calories, you could eat 200 calories at breakfast, 100 calories at lunch, and another 200 calories at dinner. You could also try two meals instead of three, eating 250 calories at breakfast or lunch and then 250 calories at dinner.
It is not easy to shift from eating normally every day to eating only 500600 calories on two days. Start by slowly reducing your calorie consumption on fasting days. For example, during the first week, reduce your intake from 2,000 calories to 1,500 calories. Continue to gradually reduce your intake until youre eating the recommended 500600 calories on fasting days.
Beverages other than water, black coffee, or herbal tea
No foods are technically off-limits
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What Are The Concerns Around A Keto/if Diet
I never like ruling a theory or idea outparticularly when its an eating approach that we know very little about I could find no published research studies that have examined the effects of the combination in regards to metabolism, health or weight loss. But at the same time, the fact that we dont know muchin terms of safety, metabolism, effectiveness, and impact on long-term healthis also the problem.
One of my biggest concerns is the lack of essential nutrients that a keto diet provides. When you rule out grains, starchy vegetables, most dairy, and fruits, its almost impossible to meet daily intake recommendations for fiber, folate, vitamin C, potassium, calcium, and Vitamin D. Because of this, a keto approach isnt a healthy long-term approach for most individuals in terms of overall health and disease prevention.
My other concern stems from the suggested benefits. I agree that very low-calorie diets are not practical and usually not maintainable, partly because the body adjusts to a lower calorie level. I can also see how appetite suppression might be a nice perk, not only when trying to lose weight, but also when fasting. But because of the appetite suppression and high level of fat intake, its almost impossible to consume all daily calories in an 8-hour window.
Blood Sugar And Other Tests During Fasting
When I fast on just chicken broth my blood glucose drops to 65 and then on the 5th day to 55 mg/dl.Have you observed a drop like this in your fasting patients?
We often see this drop during fasting.
Should i worry if my blood sugar while fasting goes up to in the 140s ?
This is quite common, and due to the breakdown of glycogen or the production of new glucose in response to some of the hormonal changes of fasting. It is neither good nor bad.
Think of it this way. Your body is simply moving sugar from its stores and pushing it into the blood. Here your body has a chance to burn it off.
I purchased a glucose and ketone meter last week. Measured my glucose on Friday after fasting for about 21 hours and the reading was 3.6 mmol with the ketones at 1.9 mmol. It worried me a bit that the glucose was this low, should I be worried? On Saturday I went for a 6 km trail run at a high tempo and my glucose reading afterward were 2,4 mmol. I would like to stay in ketosis, but my fluctuating glucose readings are making me nervous. I do not experience any of the low glucose symptoms, but I tend to become paranoid when the numbers dont look right!
Listen to your body. If you feel unwell, then stop. Otherwise, if you are worried, reduce the fasting duration.
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How I Lost 20 Pounds In A Month With Intermittent Fasting
David is a biomedical scientific officer and writer who uses intermittent fasting as part of his own health and fitness regimen.
I lost 20 pounds in 30 days by skipping breakfast, eating a light lunch, and enjoying a big, nourishing dinner.
A few weeks ago I started to notice that my weight was creeping up a bit. I guess Id been ignoring it for a while, but now it had got to the point where my jeans were feeling rather tight at the waist. So I decided to take action and do something about it.
Just one month later I was 20 pounds lighter and my jeans were looser around the waist than they had ever been. It wasnt difficult, but it did require a bit of determination. Thats the bottom line with weight loss you have to decide you are going to do it no matter what. So if youd like to do the same as I did, this is how I lost 20 pounds in just a month.
This Then Begs The Question Of What Is A Significant Number Of Calories
The true answer to this we do not know, but there is one frequently mentioned study that is said to have examined the impact of including BCAAs in a morning fast, which equated to 50 calories – and it was found that there was no significant effect on weight loss.
While the source of this information or study is unknown, this is largely where the rationale comes for an insignificant number of calories equated to 50 or less.
In food terms, this would also suggest that tea or coffee enjoyed with a dash of milk, a few berries, or some plain vegetables such as cucumber or carrots, will disturb the metabolic processes that give fasting its benefits, especially if it fends off hunger.
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If You Need To Lose Weight A Diet That Focuses Mainly On When You Eat May Be A Good Way To Shed Pounds And Improve Your Cardiovascular Health
Anyone who’s tried different weight-lossdiets is probably familiar with their pitfalls. Low-calorie diets often leave you tired, hungry, and cranky. Low-carb or “keto” diets can cause cravings and constipation. Low-fat diets are also tough to follow and, contrary to popular belief, they do not seem to prevent cardiovascular disease.
Another diet trend, intermittent fasting, takes a different approach. Rather than limiting what you eat, this diet limits when you eat . For some people, that change may be easier to manage, says Dr. Eric Rimm, professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health.
Short-term studies suggest that people stick to intermittent fasting diets as well as or better than they do to other diets. And according to a 2019 review article in the journal Nutrients, intermittent fasting promotes weight loss and may reduce risk factors linked to heart disease, including diabetes, high blood pressure, unhealthy blood lipid levels, and inflammation.
“However, we don’t have much evidence about how well this diet works over the long term,” says Dr. Rimm, noting that there are just two long-term studies of intermittent fasting, each lasting a year. Nor are there large populations of people who’ve followed this eating pattern for years. That’s in contrast to two other diets linked to a healthy heart and healthy body size the Mediterranean diet and a vegetarian diet.
Intermittent Fasting: Everything You Need To Know
Intermittent fasting may improve fat loss and allow you to eat more cheat foods than a traditional diet, but how do you do it, and how does it work? Jim Stoppani, Ph.D., has your answers!
I believe in thoroughly enjoying life and enjoying delicious foods, but I’m also passionate about maintaining a lean, muscular physique. These two pursuits, if you’ve never personally tried juggling them before, can be extremely difficult to balance.
That’s why I’ve been following an intermittent-fasting eating plan full time for a while. With intermittent fasting, you can eat the foods you wantâwithin reason, of courseâwithout packing on a ton of fat. But I’m not just now hopping on the intermittent-fasting bandwagon I’ve been a proponent of it for many years.
In fact, more than a decade ago, researchers from Yale University School of Medicine alongside a team at the University of Copenhagen explored fasting and fat loss, and their positive results in the lab have helped in my own pursuit of a lean physique ever since!
If, like me, you’re interested in keeping body fat low while enjoying some of your favorite foods along the way, IF may be exactly what you’ve been looking for. To help you decide, I’m going to answer some common questions about IF and offer some useful tips so you can get the most out of your fasting program.
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Answers To The Most Common Intermittent Fasting Questions
Welcome to the first Reader Mailbag!
Im taking a page from the playbook of one of my favorite sportswriters, Bill Simmons, and answering a boatload of your questions today.
Questions are rolling in all the time mostly through the free newsletter or and I love hearing from you. Keep them coming! I’m happy to help however I can.
My hope is that this mailbag will bring useful answers together in one place and make it easier for you to find the information you need to make the changes you want. My goal is always to make it easier for you to lose fat, gain muscle, and live healthy.
Boom. Lets get this party rolling.
As always, these are real emails from real readers.
Questions About Exercise And Intermittent Fasting
A lot of people have questions about how to exercise and train while fasting. Here are some good questions that should push you in the right direction with your training.
I wanted to thank you both for writing such a fantastic, motivating blog and for introducing me to intermittent fasting. I am enjoying watching my weight go down by basically doing something that involves no effort skipping breakfast! I was hoping you could elaborate more on your exercise routine. I have waded through the Leangains site and the other links you mentioned in the beginner’s guide, and while very interesting, they are WAY too complex for me at this stage.Paul S.
Readers like Paul are what make our community great. He read about an idea that interested him and even though some of the details were overwhelming, he didn’t let that prevent him from taking action. In other words, he started before he felt ready.
I try to make my writing as easy as possible to use, but it’s always up to you to experiment and see if it makes sense for your circumstances. Keep up the good work, Paul!
Back to the question
Intermittent fasting works great with most strength training programs.
I believe in strength training and compound movements. I think 99% of the population could get in the best shape of their life with only eight exercises: snatch, clean and jerk, squat, bench press, deadlift, pushups, pullups, and sprints. If you did those exercises and did them well, then that’s all you would ever need.
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Consider The Intermittent Fasting Plan Right For You:
Some of the popular regimens include:
The 16:8 diet, or time-restricted feeding, where you fast for 16 hours a day, but are free to eat whatever you want in the other eight hours. Experts advise picking an eating window that lets you finish your meals fairly early, such as 10 a.m. to 6 p.m. or earlier, because your body is less efficient at putting sugar away as the day goes by.
Alternate day fasting, which means limiting yourself to 500 calories one day, then eating whatever you want the next, and then repeating that process.
The 5:2 plan, which means incorporating two non-consecutive fast days into your week, then eating normally during the other days.
Here are four tips to keep your plan on track:
The Keys To Making Intermittent Fasting Work
There are two major keys to intermittent fasting success: short fasting periods and “normal” calorie intake.
- One secret behind this fasting method is that extremely low- or no-calorie intake is only for short periods. If fasting continued without a return to normal calorie intake, then the body’s metabolism will slow down. But, short periods like the 5:2 or 16:8 approach appear to maintain calorie burning. The constant flux of fasting and normal intake keeps the body on its toes, rather than allowing it to slow.
- The other key to success is not equating normal intake to binging or excessive intake. “Normal intake” refers to taking in the body’s estimated calorie needs with a healthy variety of foods. It doesn’t mean taking in excessive calories or binging on favorite foods.
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Positive Effects Of If Beyond Weight Loss And Type 2 Diabetes
Lots of people get relief from indigestion when they start a LCHF diet. Why is that? I need to convince my nephew that LCHF is his best approach and at 23 years old, nutrition isnt really his thing so I cant convince him to read your blog! He gets terrible heartburn and Im sure it is due to his high carb, high soda diet!
My guess is that there are two main effects. One, the focus on real food rather than highly processed ones is very important to maintain normal function of the GI system. Two, losing weight often improves symptoms of reflux.
Dr. Fung I am 70 and overweight, but have lost 30 lbs on the LCHF diet over about 6 months. Initially, my BP also dropped and my doctor took me off my BP meds because of the lightheadedness I experienced with the BP drop. But, now my BP is up again, even with the addition of ramipril, and my weight loss has stalled. I am still at a BMI of about 30. Do you think the 16:8 IF might help both theses issues?
The link between BP and diet is not quite as tight as with blood sugars. I think trying a 16:8 IF sure couldnt hurt.
There is not much literature about fasting and change in thyroid dosing, so I cant help you there, but I have heard several anecdotal cases of the same thing happening where thyroid function suddenly improves. With the high blood sugars, the only thing to do is to continue with your plan. It certainly seems that you are now mobilizing some of that stored sugar.
Reduce Stress And Improve Mental Health
The 16:8 diet help reduce cortisol levels and help reduce inflammation. Plus, since you wont be dealing with hunger for two days a week, its better for your mental health.
Those whove tried the 16:8 diet say how much more productive they are during fasting hours, spending less time stressing over food and more time channelling their energy into other beneficial tasks throughout the day.
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Intermittent Fasting Weight Loss
One of the main benefits of an 18:6 intermittent fasting is weight loss. There were many cases of weight loss success with intermittent fasting 18:6, as well as those where people were not that satisfied with the 18:6 intermittent fasting results. So, at the end of the day, the result depends on how well you adjust to this eating pattern, and what your choice of food is.
There are a lot of ways in which intermittent fasting can help you lose weight. Here are some of them :