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Intermittent Low-Carb Dieting - Diet Disaster


Research consistently shows that following a low-carb nutrition plan leads to better health outcomes than a low-fat diet. We’ve discussed this many times in the past. Swedish diet doctor and low-carb advocate Dr. Andreas Eenfeldt assembled 17 random controlled studies showing the benefits of low-carb nutrition. These are solid research studies as opposed to many of the observational studies that make news headlines.

Another study was just published in the journal Diabetologia showing that those on a low-carbohydrate diet had significantly better blood sugar control than those on a low-fat diet. The studies with diabetic patients are always fascinating since many people with Type II diabetes are still instructed to follow a low-fat diet and use more insulin, rather than being steered toward a low-carb diet.

With the significant amount of research supporting low-carb nutrition, there does seem to be a growing number of people reducing their carbohydrate intake. Dr. Eenfeldt, in a recent lecture, explained that in Sweden more than 20% of the population is consciously reducing their carbohydrate intake.

Following a reduced-carbohydrate diet results in very consistent changes in people, including a reduction in appetite, steadier energy levels throughout the day, possible weight loss (depending on their current body composition), lower fasting blood sugar and triglyceride levels, and many other benefits. Some of these changes take place quickly. Reductions in blood sugar levels often take place in a week or less.

Important note: If you take medication to control your blood sugar, it is important to work with a physician knowledgeable in nutrition before significantly reducing your carbohydrate intake. Since a low-carbohydrate diet lowers blood sugar levels, using the same amount of medication may result in hypoglycemia. A reduction in medication may be necessary as you gain better control of your blood sugar levels.

Intermittent Low-Carb Diets

Over the past couple of years, I’ve spoken with many people who claimed to follow a low-carbohydrate diet. They had their fair share of bacon, butter, meat and cheese, and often did a great job of eating plenty of non-starchy vegetables as well. Many would wonder why they weren’t feeling better or getting better results. With a little more prodding, they’d explain that while they were eating all of the foods commonly a part of  a low-carbohydrate nutrition plan, they’d still treat themselves on occasion, which is where I started thinking of them as following an intermittent low-carb nutrition plan as opposed to a legitimate low-carb nutrition plan.  Is there a big difference between the two? Absolutely!

When individuals follow a low-carb diet for an extended period of time, their carbohydrate consumption is far less than the average person. Without significant amounts of carbohydrates, the body shifts to its preferred source of fuel, which is fat. Some people make this shift quickly, while others can take days or weeks to transition. During this transitional period, some people find they actually have a reduced level of energy and strong cravings for the carbohydrate-rich foods that were previously part of their diet.

For those who succumb to their cravings, a snack or meal of carbohydrate-rich foods shifts their body back to using carbohydrates for fuel. Of course, the high level of carbohydrates raises insulin levels, increasing fat storage and reducing fat burning. Some people would admit they were snacking on carbohydrate-rich foods each day. Others would admit they’d “treat” themselves once a week. Even large amounts of alcohol like beer and mixed drinks can affect the body’s ability to burn fat as they contain higher levels of carbohydrates.

From a metabolic standpoint, this can be really confusing to the body. For a few days, the body may transition to using more fat for fuel, then carbohydrates are reintroduced and it has to shift back to burning sugar. Then the transition to fat begins again and before the major benefits of a reduced-carbohydrate nutrition plan take place, carbohydrates are consumed once again.

When people think of the majority of foods they eat, they tend to think of the most common lunch, dinner and breakfast they eat. Many people who say they follow a low-carbohydrate diet think of the foods that make up the majority of their diet, and think they follow a low-carbohydrate nutrition plan. But the benefits of low-carbohydrate diets come from following it all the time, not on an intermittent basis.

The following are five suggestions to help you stay on a real low-carbohydrate diet, and avoid the pitfalls of an intermittent low-carb diet.

5 Ways to Avoid Intermittent Low-Carbing

1. If you don’t have it at home, you can’t eat it at home

The most commonly cited reason for low-carb nutrition plans not working is that many people don’t stick with them. There are about 50,000 foods in the average supermarket, and the vast majority are rich in sugar or starch. If you don’t buy those foods, you won’t be tempted at home. And no one in your home needs them. The reason so many people have a hard time sticking with their plan is they still buy the foods they know they shouldn't have in the house. 

2. Eat what you should eat, not what your friends want you to eat

Do you feel swayed by your friends? The next time they want you to eat what they eat, think of this statistic recently announced in Medical News Today: By 2025, 53.1 million Americans will have diabetes, a 64% increase from 2010! That’s just one of the major diseases that will be increasingly common among your friends if our population doesn’t change its diet and lifestyle. Don’t let their future health influence yours. If this makes you uncomfortable, consider spending time with your friends outside of meal times. 

3. When you’re out, ask for modifications

Virtually any restaurant can make accommodations and, generally, you can have a great meal without eating the starch. Ask for double vegetables instead, even if it costs a little more. I can’t remember the last time I ate out and ordered exactly what was on the menu. The more you do it, the easier it becomes. If the food is being provided for you, find out what it is in advance. If none of the food would be something you’d eat, bring your own or skip the meal. A little fasting might be good for you.

3. Realize there are greater pleasures in life than sugar and starch

Food is certainly one of life’s pleasures. But the problem is that our sense of taste is very distorted from exposure to increasingly sweet foods. When I fly, I usually order club soda for something to drink. I always carry a bottle of water, so the carbonation gives me a little variety. On a recent flight, I ordered my usual beverage. Of course, I didn’t get the full can, just the little cup ¾ filled with ice. I took a sip and in less than a second, I wanted to spit it out. Rather than getting club soda, the flight attendant had brought me Sprite. It has been at least 20 years since I’ve had regular soda, and a couple  of years since having diet soda. The taste was sickening.

When you don’t eat or drink sugary foods and beverages, your sense of taste changes over time. If you give up sweet and starchy foods, you’ll likely gain a greater appreciation for natural foods and the variety of pleasurable tastes they have. In time, you may find that finishing a meal with half a cup of mixed berries and a little heavy cream provides just as much pleasure as a piece of cake or a bowl of ice cream did in the past.

4. Commit to your plan for 30 days

As Drs. Jeff Volek and Stephen Phinney explain in The Art and Science of Low Carbohydrate Living, it can take 2 to 4 weeks to fully adapt to reduced carbohydrates in the diet. Unfortunately, people often find themselves snacking on their old junk food choices long before they fully realize the benefits. Those who stay with the plan for at least 30 days often realize how much better they feel and perform, and are impressed with how their body composition changes. After realizing the benefits, and being able to enjoy life and food for a month without the junk foods common in the Standard American Diet, people often realize how much better life can be without those foods. A 30-day commitment includes weekends and work lunches, so when you begin the commitment, don’t let others talk you off your plan.

5. Learn to cook

Cooking does not need to be complicated or time-consuming. In fact, it can save you time if you cook in bulk and make meals that you can reheat as the week goes on. If you  eat out often, you’ll have to be prepared for a lot more challenges than if you cook the food yourself. There are dozens of cookbooks available if you need some ideas. We’ve also provided some recipes on this site, which you can find in the “Recipes” category on the right.


Following a lower-carb nutrition plan is effective for weight management, and has been shown to improve lipid and glucose levels, reduce hunger, stabilize energy levels and lower blood pressure. It also helps an individual avoid other issues related to high starch and sugar intake. However, it’s most effective when people follow it on a regular basis. As Dr. William Davis recently explained in a lecture, the negative effects on lipid levels from a single meal of excessive sugar or starch can last up to a week. Intermittent low-carb eating is not the same as following a lower-carb diet. To reap the rewards, you must look at it as a lifestyle, not a diet. If you have a habit of telling yourself you follow low-carb but still snack on occasion, consider rethinking how you talk about your nutrition habits. You may find you’re not fooling others, but may be fooling yourself.

Written By Tom Nikkola - Director of Nutrition & Weight Management

This article is not intended for the treatment or prevention of disease, nor as a substitute for medical treatment, nor as an alternative to medical advice. Use of recommendations in this and other articles is at the choice and risk of the reader.

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Reader Comments (15)

Tom, when following a low-carb 'diet' (I am hesitant to use the word diet because it is more of a lifestyle than a diet), what percentage of calories do you recommend come from fat versus protein? If someone is following a ketogenic diet, is there a point where consuming too much fat at one time or in one day that the body stops burning fat and will store it instead? How do you know what is amount of fat/protein is too much? Thanks!

June 9, 2012 | Unregistered Commentermelanie

Hi Tom,

I really appreciate your columns it is great to see them because there is so much contradictory information out there. I've been reading a great deal about low carb high fat lately. I'm also familiar with Atkins.

Still I am a little confusion, because if one stays under 50 grams, or less than 20 grams does it really matter if one eats sugar or wheat. I'm thinking about the French and Japanese paradoxes. They ate grain, but not much sugar and had low incidents of obesity and heart disease.

About a month ago I was reading Gary Taube’s book Why We Get Fat and he returned me to Atkins which I had not thought about in about 5 years. I now realized that I must follow a low carb life style.

When thinking about it I realize the hyper activity in my autistic son and the ADHD my daughter was exhibiting might be related to their blood sugar so I reduced the sugar in their diet, but I can't seem to eliminate it. I also increased their fat intake. I bought Trader Joe’s full-fat yogurt, which has added sugar -- honey. My kids are less hyper, but they are 5 and 8 so they eat at school and it is really hard to have them eat low carb.

My son’s teacher was supportive, but my 5 year old son was refusing to eat his packed lunch and was trying to take his classmates food so I had to let him eat the cafeteria food he was used to. My daughter would eat her lunch, but she really wants the sweets and pizza and fries that I had been mindless feeding her for years. I’ve let her have it infrequently since making the diet change. My children are not overweight, so I only notice the sugar problem because of behavioral issues.

I know I must follow a low card life style. However, with my kids I have been taking a gradual approach. I am cooking with more fat, more meat and I’m giving them less sugar i.e. no more go-gurts, fruit juice or Capri Suns. No more crackers, bread, chips, cookies and pasta but yes to yogurt, berries, and apples and whip cream. It is so hard to find information about feeding children when it's all pizza, cake, soda, candy and the food pyramid.

It makes me think about the paradox. I mean should I just reduce the sugar, but let them have rice and a French baguette and if so how much. I am confused because before refined flour and sugar in everything Americans had little heart disease and obesity. I am sure sugar is a problem, but I’m not sure if the problem is wheat or refined flour, and is the problem all rice or white rice. My son only likes starchy veggies like corn, peas and carrots. I’ve got to pick my battles. He gets lots of dairy, because he likes it and it does not seem to raise his blood sugar.

Is there some safe dose?

Are the people you mentioned exceeding 50 grams? Or, is any gram a gram too many. I guess I know total carbs is an individualized issue, but still I’m sure there is a toxic level of sugar.

June 10, 2012 | Unregistered CommenterEllen

What percent of the recommended daily value of carbohydrates do you recommend for a low-carb lifestyle?

June 10, 2012 | Unregistered CommenterRebecca

My family history has diabetes (type2) on both sides.I have Ovid and my insulin levels are always high(46) I take 1750mg of metformin.What kind of diet should I follow.

June 11, 2012 | Unregistered Commenterdianna

@Melanie: I hate to fall back on the fact that everyone is different, but they really are. For the most part, if people focus on getting most of their food through non-starchy vegetables, a little fruit and then protein sources (meat, fish, poultry, protein powder, etc.), nuts, seeds, etc, they'll get enough to energy for their daily needs. Adding grass-fed butter or other healthy fats is usually okay for giving more flavor to food. To your question of "at what point will the extra fat lead to fat storage?" it's actually difficult to say because there hasn't been much research done on the topic. Theoretically, if someone keeps insulin levels low by avoiding excessive carb intake, they shouldn't store fat because their fat cells won't get the signal to store it. Those extra calories could then be burned off as heat or through activity. I've just never seen a solid study where people were kept on a low carbohydrate diet and then overfed fat to see what happens. There are a lot of anecdotal stories, but nothing in the research. Having said all that, I'm going to try to address the topic of carbohydrate levels in an article that should post in a few weeks.

@Ellen: Thank you. You should be applauded for the action you've taken with your kids foods. It can be a challenge with all the junk their friends may be exposed to, but it's great to see your making an attempt. To your question about wheat and sugar, I think what you're asking is, "If I keep my carbs under 50 grams, does it matter where they come from?" My answer would be, probably. If someone eats a ton of carbs, like in the Standard American Diet, it would be a huge accomplishment to just reduce their total intake, where it's under 100 grams or 50 grams. That said, wheat does have the potential to create digestive issues even in very small doses. In addition, as Dr. Davis explained in our interview (search "Dr. Davis" in the search bar at the top of the page), wheat can also act on the brain in a way to create addiction. If that's the case, it can leave people feeling like they're constantly craving the foods that were once part of their diet. It's possible sugar could have a similar reaction. So while there are a lot of benefits to be gained from simply lowering carbohydrate consumption to a more natural level, removing those foods would be even better. Will you completely eliminate sugar? No, and I don't think you have to worry about it. Can you completely eliminate wheat? Yes, and it's pretty easy to do so. I hope that helps. Great work with what you're doing with your kids.

June 11, 2012 | Unregistered CommenterTom Nikkola

@Rebecca: I'll be addressing this in an upcoming post. Rather than thinking of it as a percentage of the diet, most experts focus on grams. The reason is, if you consume a relatively low total amount of calories, like 1600, 100 grams of carbohydrate would provide 25% of the total intake in the diet. However, if you're really physically active and consume 3200 calories per day, but maintain the same 100 gram total each day, it would only provide 12.5% of the calories in the diet. I'll review what research has shown to be beneficial, and how targets of 20 grams, 50 grams, 100 grams and 150 grams are used in research and practice. Much of this depends on an individual's body composition, blood chemistry, activity level, etc. I hope to get the article posted in the first half of July.

@Dianna: If you're considering a low carbohydrate diet while on Metformain (or any other medication that affects blood sugar levels), it's really important to work with a physician who has experience with using reduced carb diets to control diabetes. I recently met Dr. Helen Hilts, a physician in Scottsdale who has focused her practice on using low-carb diets to reverse the effects of diabetes. Her website is I'm not sure where you live, but you could start there and see if she knows of someone near where you live.

June 11, 2012 | Unregistered CommenterTom Nikkola

These types of articles drive me crazy. Plants are carbs, plants have proteins, The BEST diet is one balanced with COMPLEX carbs, ethical and healthy raised meat protein, and healthy fats. Any meat or plant protein that is raised with chemicals, hormones, pesticides or unnatural feed is far more unhealthy than anything we can put in out body. The brain MUST have carbs to function properly. WE SHOULD EAT CARBS...LOTS OF CARBS. What we dont want are simple carbs. Plants are not the enemy, they are one of the best things that we can possible eat. Sugar and food that convert to sugar is the enemy. This article fails to clarify this. All carbs are not created equal just as not all proteins are created equal. It just frustrates me so much when people write about low carb diets without clarification. This is simply bad education. I am by no means a vegetarian, but I love Michael Pollan's quote..."Eat food, mostly plants" I know where my protein comes from. I eat healthy fats and GASP, CARBS - complex carbs.

June 11, 2012 | Unregistered CommenterDina


June 11, 2012 | Unregistered CommenterPaul

Dina: I am almost certain that after reading the title and the article itself, that the author's intention was not to use this particular article to dissect the components of low carb diets and further discuss the difference in sources of carbohydrates. Several actual studies are listed, supporting the low carb lifestyle. It may be beneficial for you to read some of these studies and reach out to other sources that show the evidence supporting low carb living. (there are even links WITHIN this article to hep guide people interested in more information about low carb living and differences in 'good' versus 'bad' carbs. The purpose of this article, again based on topic and general content, was not to tell people to avoid every type of carbohydrate. Furthermore, no where in the article did the author state that all carbs are bad, that people should avoid vegetables, or that they should eat meat/protein from whatever source they can find. He simply is cautioning people from following 'low carb' lifestyles only part of the time...and stressing the fact that doing it 'half heartedly' is not going to work. He walks the reader through common sources of 'intermittent low carb living' and ways to avoid getting off track. Its ONE article, with more to follow...keep that in mind...

June 11, 2012 | Unregistered Commentermelanie

what happened to the evidenced-based requirement of consuming at least 130 grams of carbs per day in order to supply adequate glucose to the brain? Also, studies show that a low-carb diet will cause our glycogen stores to become depleted causing our bodies to rely on lean muscle tissue from our muscles and organs for energy.

Can you please comment on these ideas and provide meta-analysis that disprove these beliefs?

June 12, 2012 | Unregistered CommenterMJ

@ MJ

I suggest reading the intro to Volek & Phinney's book "the Art & Science of Low Carb Living" as it provides sound scientific evidence that humans can adapt very successfully to a dietary carbohydrate intake well below the range you mention. Adaptation takes time, but it's very possible thanks to our liver being able to make rather large quantities of glucose and/or ketones for our brain to run on. The side-effects of such a drastic reduction is carbohydrates (if done properly with LOTS of dietary fat intake) are often things like reduced inflammation, loss of body fat and maintenance of lean tissue, and increased feelings of satiety/decreased cravings. Some people may look/feel like a newer version of themselves if they adopt this lifestyle.

June 13, 2012 | Unregistered CommenterPaul Kriegler, RD/LD

True. we need self commitment to be able to engaged in weight loss regimen. It's not a joke to comit but once we are there, we should hold on to our decision.,

June 20, 2012 | Unregistered Commenterarcher

Hello Tom,
Those 5 Ways to Avoid Intermittent Low-Carbing was very helpful to me. I am also one of them who loves to have a healthy diet thanks for letting me know all about the disaster of low carb dieting. I will surely note down this point for my further usage.

June 22, 2012 | Unregistered Commenterethan

The gov't says that 300mg of Carbohydrates are the norm for a healthy diet. (The pyramid). What constitutes low. You do have to consume some Carbs. If going on and off the low carb diet is bad then, how many can it vary?

June 25, 2012 | Unregistered CommenterPaul

Some commenters just can't seem to grasp that vegatables are carbohydrates. So on a low carb diet if you increase your consumption of vegatables which have essential nutrients, and decrease your consumption of grains which do not have essential nutrients are you better or worse off?

I mean if instead of big sandwich you just skip the bread and make big salad with health oils, healthy vegatables, and healthy protein are you really worse off?

Man what is with those low carbers eating omelets with vegatable for breakfast, and salads with protein for lunch, and dinner with some meat and vegatable. I mean don't they know they are killing themselves. How dare they skip the glucose ride of the S.A.D.?

How could one pass up cereal for breakfast, a sandwich for lunch, a candy bar for a snack, and pasta with sugar for dinner?

Silly me.

June 25, 2012 | Unregistered CommenterEllen

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