Top 5 Diet & Weight Loss Myths vs. the Real Facts

debunking diet mythsSo-called diet “experts” can often offer confusing and conflicting advice. Simple carbs are the cause of your expanding waistline one week; fruits and sugars are  the culprits the next. A low-fat diet is key to losing weight – or is it a low-carb diet?

Dieting advice is mind-bogglingly complicated and ever-changing. It can lead you to make poor decisions about what you eat, and even prevent you from reaching your weight loss goal.

While you can’t always rely on diet experts to offer wisdom, here is something that never fails: Advice from peer-reviewed scientific studies. Using science-proven facts, many common dieting mistakes and myths can be dispelled. Once you are aware of these facts, you will be on your way to a healthier lifestyle

Common Dieting Myths & Mistakes

Myth #1: Skipping Breakfast Slows Down Your Metabolism

Nearly all diet magazines and websites claim that skipping a healthy breakfast can harm your weight loss goals. Some settle on the claim that eating breakfast will make you less likely to binge during lunch, which certainly is not an outrageous claim by any means. But some go further by claiming that not eating breakfast can slow your metabolism, making it harder to burn calories.

The Reality
Studies show a direct correlation between eating breakfast and consuming fewer calories, but scientists have never established a link between poor breakfast-eating habits and a poor metabolism. Moreover, the people in these studies show that people who eat breakfast generally exhibit better lifestyle habits, such as being more physically active and having a lower fat intake.

However, correlation is not causation. Anecdotal evidence shows that people can skip breakfast while still losing weight and body fat – such as the results demonstrated by those who practice intermittent fasting.

The Bottom Line
If skipping breakfast makes you more likely to binge later in the day, don’t skip it. However, if you do not feel genuinely hungry, don’t force yourself to eat.

couple eating breakfast

Myth #2: Frequent Meals Speed Up the Metabolism

If you really want to rev up that metabolism – and you do, if you want to keep losing weight – many diet experts say a key is to eat frequent, small healthy meals. Constantly delivering a steady stream of calories into your body supposedly keeps your metabolism high, allowing you to lose weight with less effort. Some even go so far as to say it’s been scientifically proven, but that’s not necessarily the case.

The Reality
Though many studies have been conducted, more than 10 have not established a link between frequent eating and weight loss. Furthermore, a scientific review published in the “British Journal of Nutrition” evaluated those that did find a relationship and concluded that results were likely skewed by two factors: under-reporting of meal frequency, and change in dietary habits after the studies commenced.

It also reviewed studies refuting a link between frequent meals and metabolic increase, and concluded that meal frequency rarely improved weight loss – a fact that contradicts the advice you’ll find in many diet magazines or articles.

The Bottom Line
If you want to lose weight, frequent eating isn’t necessarily a reliable diet strategy. If you genuinely like eating smaller, more frequent meals, go for it, but don’t force yourself to eat more meals in hopes of losing weight. In addition, if you’re trying to make yourself eat more frequently, you could end up consuming more calories, which, as we all know, will lead to weight gain.

muscular man small meal

Myth #3: Foods With a Low Glycemic Index Promote Weight Loss and Satiety

To lose weight – and to reduce the pangs of hunger – many diet experts recommend eating foods with a low glycemic index, or GI. Foods that break down quickly, such as white bread and white rice, are considered to be high-GI and not good for losing weight; foods that break down the slowest, such as whole grains, vegetables and nuts, are considered low-GI, or good for losing weight.

Some diet experts claim that high-GI foods can cause blood sugar instability, which in turn causes people to feel hungry faster, leading to overeating and snacking. Supposedly, this blood sugar instability may even make a person insulin resistant, which is linked to diabetes.

The Reality
While the science seems convincing, studies conducted on the glycemic index often return mixed results. In a 1996 study published by the “American Journal of Clinical Nutrition,” healthy men who ate a high-GI diet for 30 days were less insulin-resistant than the men who ate a low-GI diet. However, their weight did not increase, which is contrary to what most experts expect from high-GI food consumption.

Furthermore, a scientific review of 31 studies did not conclusively show that low-GI foods suppressed appetite. Of the 31 aforementioned studies, 15 studies showed greater satiety associated with low-GI diets, but a majority 16 studies showed low-GI diets did not suppress the appetite.

The Bottom Line
The results aren’t conclusive, but there is not enough evidence to suggest that avoiding high-GI foods are necessary to feel fuller longer, lose weight, or reduce your risk of diabetes. While you shouldn’t eat high-GI foods in excess, you don’t necessarily need to avoid all high-GI foods to lose weight.

cutting calories is the key to weight loss

Myth #4: High Fructose Corn Syrup Makes You Fat

Obesity has been on the rise since the 1970s – and, incidentally, so has the use of high fructose corn syrup (HFCS), which some regard as being the key ingredient responsible for the obesity epidemic. Diet experts often recommend skipping food products sweetened with HFCS as part of a healthy diet plan.

The Reality
While HFCS is correlated with obesity, several peer-reviewed studies and reviews challenge many of its supposed obesity-causing properties. A review created by the American Medical Association points out that the consumption of all high-caloric sweeteners, not just HFCS, rose along with total calorie consumption, so HFCS alone is not responsible for the obesity epidemic.

Furthermore, since the 1970s, obesity has also increased in countries where HFCS is not heavily consumed, such as Mexico. Conversely, HFCS consumption has also increased in countries where obesity is not an epidemic, such as South Korea, which has one of the lowest obesity rates in the world.

The Bottom Line
If you want to eat a certain food but are afraid to because it contains HFCS, don’t stress out. Occasionally consuming a HFCS-containing food product won’t make you fat. What makes you fat is the consumption of too many calories, regardless of the source. Remember, moderation is key!

moderation is key

Myth #5: “Eat Clean” to Lose Weight

Here’s a common phrase you’ll see in diet magazines: “eat clean.” By its definition, eating clean has many meanings, but most experts define clean eating as eating superfoods rich in micronutrients (such as vitamins) that are not processed and are low in fat and “bad carbs.”

For example, clean eaters often think organic vegetables, lean meats, legumes, and whole grains are extremely clean, whereas foods such as hamburgers, fruits, whole milk, and white bread are unclean.

The Reality
While there are some nice nutritional components to clean eating, it isn’t necessarily a better way to lose weight. Clean eaters often ignore the golden principle of weight loss: weight loss occurs in a caloric deficit, regardless of the source of the calories. If you eat in a caloric surplus while eating clean, you will gain weight.

However, it should be noted that while you can gain weight with any type of caloric surplus, clean and healthy eating does advocate eating more non-processed foods, which contain more vitamins and minerals and less of the bad stuff (such as excess fat, salt, and sugar).

There’s also the issue that clean eating prescribes rigid eating behavior. A 2001 study reported in the journal “Appetite” associated a higher body mass index (BMI) with people who followed or tried to follow a rigid diet without allowing any flexibility in their diet plan.

The Bottom Line
Eating clean alone will not help you lose weight if you’re eating too many calories. You need to watch your caloric intake just as you would with any processed foods. Focus on eating mostly minimally processed, micronutrient-rich foods while watching your caloric intake for better health and weight loss success.

If you can fit a serving of ice cream or chips into the mix, do so in moderation, but only if it fits into your calorie goals. Eating a half of cup of ice cream once or twice a week is fine; eating a half a pint of ice cream in a single serving is not fine.

woman no cake diet

Final Word

Diet magazines, websites, and even diet experts often over-complicate dieting, when in fact simply eating a calorie-controlled diet composed mostly of wholesome foods can help you reach your weight loss goals. Manipulating your metabolism, fearing certain foods, or timing your meals isn’t necessary.

If you’re having trouble losing weight, check your calorie count first – you’re probably eating too much or too little.  Of course, exercise is important too, and most effective weight loss plans require regular exercise combined with eating healthy meals as a way to stay fit while keeping off the weight.

What are your thoughts on diet myths? What other tips do you have for losing weight and eating healthy?

  • Anonymous

    Pure and simple, no matter what you eat, it is the number of calories you consume that influences weight gain or loss. However, I eat a lot, but I exercise a lot also. I keep track of the calories burned and that has pushed me over the years to keep exercising a lot. If the amount of exercise is reduced over what I normally do, I immediately start gaining weight. Exercise and healthy food is the key to avoiding weight gain.

    • Ann Olson

      Thank you for your comment — I completely agree with you.

  • David

    Although I actually agree with many of the conclusions you’ve made, your underlying premise is broken. Your premise is that “science” has all the facts. However, that in itself is not necessarily correct. For instance, you write regarding GI intake that there are 31 studies and 15 say one thing and 16 say another. Next year, after the next 2 studies turn the tables in favor of the former, the “facts” are now exactly opposite. The problem is that Truth doesn’t change, but “scientific” conclusions do so constantly. Anyone who trusts “science” to have all the right answers will find themselves like the surf of the sea, driven and tossed by the wind. Science can be good, but it isn’t the end-all, be-all. Just ask all the dieters out there who have been listening to “science” and still have not been able to lose weight. Best answer: everything in moderation, exercise, expend more calories than you take in…

    • Ann Olson

      David, I never made the assertion science has all the facts, hence why I said “many” diet myths can be dispelled by science, not all. I actually agree with you and don’t think science can be applied to every aspect of diet, nutrition or fitness — but science can be certainly helpful if you need help separating fact from fiction.

  • Leoluca Criscione

    Dear Ann, Compliment for these clear ‘facts’! What you describe here, belongs to the chapter: “Science feeds the confusion”, as stated also in the book “Eating healthy and dying obese”!
    The book describes, in addition, the importance of the personal energy (calories) balance for the regulation of weight and, hence, healthy! As the title reveals, the book describes in details why there is no food, which makes us thin or fat!
    The book is the basis for an educational campaign aiming to separate ‘Myths from Facts”, we start in Europe this year and will continue worldwide in the next years! I would be please to send you a copy for your use.
    Best regards from Switzerland, Leoluca Criscione, former cardiovascular and obesity researcher

    • Ann

      Is the book available in the USA ?

  • Lee “belly fat” Taylor

    Everyone is different so different types of diet plans work for each person. I eat five to six small meals per day to keep my metabolism going and I get about 45 minutes of cardio exercises in about three to four times a week. Foods that help me build muscle and burn fat are whole grains, fish or other foods high in protein. Fresh fruits and vegetables curb my sweet cravings and they improve my overall immune system. Many celebs eat 30 percent of carbs, 30 percent of proteins and 40 percent of fats in which seems to help me also.

  • Steven Charlap MD

    Hi Ann,

    Unfortunately, I have to take exception with your comments about not eating breakfast. Metabolism is affected by metabolic pathways which are affected by hormones. For example, the neuro-hormones leptin and ghrelin, among others, which act as an appetite stimulant and suppressant respectively, are affected when one has not eaten for more than several hours. It is unwise to skip breakfast also because of its affect on depleting blood sugar which is necessary for creating neurotransmitters which otherwise get depleted. I appreciate your efforts to eradicate food myths but please be careful in further confusing the populace about good eating habits. Eating breakfast is an essential part of maintaining good homeostatic balance and healthy weight (of course on the condition that the breakfast itself is healthy.)

    Steven Charlap, MD

  • Oren

    I was able to lose 22 pounds just by eating less and exercising more. I think people to make it too complicated

  • Nick Riley

    Calories in VS Calories burned. Simple as that.

  • Qwerty

    @Nick Riley

    It’s a waste of time counting calories or carbs for that matter.


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