Are these popular diet mantras fact or fiction?

Are these popular diet mantras fact or fiction?

Fact or fiction?

Dieting advice comes from all directions – on social media, in books, from celebrities and even our family and friends. It can be difficult to hear at times, especially because so many “tips” don’t actually ring true. Melodi Peters, a registered dietitian at Advocate Good Shepherd Hospital in Barrington, Ill., weighs in on some popular myths.

Myth #1 – Drinking smoothies will help you lose weight.

“Most smoothies are primarily fruit and vegetables, which are loaded with carbohydrates,” warns Peters. “The liquid smoothie leaves your stomach quickly, creating a spike in blood sugar. The insulin response following a smoothie can leave you feeling tired and hungry. My advice is to eat your fruit and vegetables. Never drink them.”

Myth #2 – Eating at night makes you fat.

Does it really matter what time of day you eat? There is no proof that late-night meals cause you to put on weight. However, we do know that consuming too many calories causes weight gain, and many night eaters do tend to overeat. Try to stick to earlier mealtimes.

Myth #3 – Athletes need a ton of extra protein.

If you are training for the Chicago Marathon or are an athlete of any kind, keep this in mind: Most diets provide plenty of protein, even for athletes. The real secret to boosting athletic strength and muscle is to get enough calories and focus on intense training.

Myth #4 – Coffee is bad for you.

Drinking two to three cups of coffee a day can be a safe part of a healthy diet. In fact, research suggests coffee may help reduce the risk of type 2 diabetes, gallstones, Parkinson’s disease and even some cancers. But for dieters trying to lose weight, avoid coffee condiments, such as cream, sugar and other flavored syrups.

Myth #5 – You should eliminate fat from your diet.

Your body needs fats as well as protein and carbohydrates. Good-for-you fats found in foods like nuts, avocado, olives and low-fat dairy give you energy, help rebuild cells and produce needed hormones. The fats to limit or avoid are saturated and trans fats found in foods like butter, high-fat dairy, red meat and many processed foods.

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  1. Susan Gills, MS, RDN November 15, 2017 at 12:42 pm · Reply

    I disagree with #2, as there is research that explores timing of energy intake as related to circadian rhythms and weights.

  2. S. Gillis—do you have a link to the research you have cited???

  3. Item #5 seems to imply that the fats in low-fat dairy differ in quality (good-for-you) from the fats in high fat dairy (to be avoided). Was this what was intended? If so, I would like to hear more detail. I thought the fat in 1% milk was the same quality, only lesser amount, than in whole milk.

  4. Susan is right. A hormone that opens fat cells to burn stored fat is released after sleep begins but only in the absence of insulin, which is produced in response to consumed carbohydrates. It matters what food groups you consume before bed.

  5. Susan, Janet – Not sure what studies you’re gathering your information from, but there are numerous, high quality studies that say exactly the opposite. In fact there was an article published in the American Journal of Clinical Nutrition that showed the exact opposite. People consuming food in the 4-hour window just before bedtime actually lost body fat (1,2).

    1. Nonino-Borges CB, Martins Borges R, Bavaresco M, Suen VMM, Moreira AC, Marchini JS. Influence of meal time on salivary circadian cortisol rhythms and weight loss in obese women. Nutr Burbank Los Angel Cty Calif. 2007;23(5):385-391. doi:10.1016/j.nut.2007.02.007.

    2. Stote KS, Baer DJ, Spears K, et al. A controlled trial of reduced meal frequency without caloric restriction in healthy, normal-weight, middle-aged adults. Am J Clin Nutr. 2007;85(4):981-988.

    Will this myth never die!

About the Author

health enews Staff
health enews Staff

health enews staff is a group of experienced writers from our Advocate Health Care sites, also including freelance or intern writers.