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9 Common Food And Nutrition Myths Debunked

9 Common Food And Nutrition Myths Debunked

By Author Name

Apr 29, 2019

Updated Oct 25, 2023

5 min read

9 Common Food And Nutrition Myths Debunked

Food can be a topic of serious contention today, and everyone seems to have an opinion on what you should and should not eat. People will have various reasons for eating or not eating certain foods and oftentimes they fall victim to food myths that have been perpetuated over time like old wives tales. We sat down with Cole Adam, a Registered Dietician in the Denver area, to finally set the record straight on some of the more common food myths.  

Q. Will consuming enough Vitamin C prevent colds?

oranges sliced on a cutting board with grapefruit

Taking a vitamin C supplement is unlikely to prevent a cold. It may, however, make a cold less severe and may shorten its duration, but the research suggesting this is limited. Vitamin C is an essential nutrient in the human diet, but instead of supplements, we should choose vitamin C-rich foods, such as: peppers, citrus fruits, dark leafy greens, broccoli, strawberries, and most other fruit.

Q. Are there side effects to low carb/no carb diets?

Woman turning down bread slices

Low-carbohydrate diets are popular for weight loss. Although these diets do lead to rapid, short-term weight loss (which is mostly water weight), the research suggests that they are no better than other weight loss diets over the long-term, and that most people following a low-carb diet gain the weight back over time. Additionally, long-term studies consistently show that adherence to a low-carb diet is associated with an increased risk of all-cause mortality. In other words, low-carb diets may lead to some perceived short-term benefits, but they are at the expense of our long-term and overall health.

Q. Are egg whites better than egg yolks?

 Bowl of fresh brown and white eggs

The research comparing egg whites to whole eggs, consistently shows that egg whites are the preferred option, as their consumption does not raise LDL (bad) cholesterol levels, which is a risk factor for cardiovascular disease, and is something we see with whole egg consumption. This is likely because the yolk is where the cholesterol and unhealthy fats are. You'll often hear that egg yolks also contain a variety of "good" nutrients, such as vitamin D, choline, and a pigment called lutein, but this is quite misleading. These nutrients are present in egg yolks, but in extremely small amounts, so the cons of eating egg yolks far outweigh the exaggerated pros.  

Q. Is a vegetarian/vegan diet more beneficial to your health than an omnivorous diet?

woman picking vegetables in a greenhouse

Large, population-based studies consistently show that those eating vegetarian or vegan tend to be healthier than those eating an omnivorous diet. They tend to have lower rates of heart disease, cancer, type-2 diabetes, and also tend to be leaner. There is a growing consensus among health professionals and health organizations that we should all aim to adopt more of a plant-based diet centered on whole grains, beans, fruits, vegetables, and nuts/seeds, while limiting or avoiding animal products and processed foods. It is also worth pointing out that a healthy plant-based diet is the only diet proven to reverse heart disease, which is the leading cause of death in the U.S. and worldwide. There are also ethical and environmental reasons to eat more plants and less animal products. I tell people this, the more whole, unprocessed, plant-based foods you include in your diet, the healthier you'll likely be.

Q. Does eating carrots help your eyesight?


Carrots are rich in beta carotene, an orange pigment that our bodies can convert into vitamin A. Vitamin A is essential for good eye health, but eating more than required will not improve eyesight. This misconception was used by the British in World War II. They had developed radar technology and their pilots were able to track and shoot down German planes at night. To keep people naïve to this new technology, they released propaganda stating that their pilots were eating a lot of carrots to boost their eyesight and help them see in the dark! 

Q. Can apple cider vinegar lower your blood sugar?

Apple cider vinegar on a table

Vinegar is a healthy condiment, but apple cider vinegar has recently gained momentum as a "superfood". Most of the health claims circulating the internet regarding apple cider vinegar are totally unsubstantiated. However, there is some research suggesting that adding vinegar to a meal can help lower post-prandial blood sugar levels. This could be any type of vinegar, however, as there doesn't appear to be anything special about apple cider vinegar. So, try to cook with more vinegar, as it may have some health benefits, but it's not a magic bullet cure-all.

Q. Are frozen fruits and veggies are less nutritious than fresh ones?

frozen vegetables in a bag

When it comes to fruits and vegetables, people often ask, which is healthier, fresh or frozen, cooked or raw? The best answer is, whichever way you'll eat them. There are a few nutrients that are inactivated when frozen, and some nutrients that are destroyed when cooked, but these details pale in comparison to the numerous health benefits obtained by simply eating more fruits and vegetables.

Q.  Are several small meals better than 3 large ones?

Two different size spaghetti plates

When it comes to health, what we eat is far more important than how often we eat. Whether we eat six small meals, or two larger meals, both can be fine, so long as they are centered on healthy foods.

Q. Does eating at night cause weight gain?

couple eating popcorn

Again, what we eat is far more important than when we eat. Eating at night is often blamed for weight gain, but it likely has more to do with what we're eating, as we tend to choose less-healthy, high-calorie foods late at night (ice cream, cookies, buttery popcorn). Most people aren't chomping on celery sticks and carrots for a late-night snack. With that being said, there may be a metabolic benefit to extending our overnight fast. Some research suggests that a longer overnight fast may help lower blood pressure, insulin sensitivity, and help with weight loss. This research is still limited, so no concrete recommendations can be made. And, if you are taking insulin, or taking any other medication that is scheduled with meals, consult with your doctor before making any changes.