Have you ever had a conversation with another parent and they just off-handedly say something about kids needing to drink 8 glasses of water a day? Or that they feel bad that they haven’t been able to get their family to eat totally vegan? Or that organic food is obviously and clearly healthier than conventional?

These food myths are viral and stick around because on one level they’re intuitive. Drinking water is indeed good for us! As are vegetables! And, hey, who doesn’t want food with less pesticide?

Sometimes our intuition will lead us astray. Today, we’re gonna bust some myths so that we can parent in the clear light of science-backed evidence!

Food Myth #1: A vegan diet is the healthiest diet.

Science says: Not so much. Eating veggies is good, and it’s totally possible for adults to plan out a vegan diet and supplement appropriately so that they’re optimally healthy. But it takes a lot of planning, and the best research shows that a whole-food, animal-protein-based diet is just as healthy as a whole-food vegan diet.

More importantly, research suggests that strict vegan diets are associated with health problems in children, and are associated with some health risks in adults, including lower birth weights for vegan mothers.

As we advocate in our Nourish Masterclass, the simplest way to ensure optimal nutrition for your family is to focus on a wide range of whole foods, including animal protein.

Food Myth #2: Everyone should drink 8 glasses of water a day.

Science says: Nah, drink when you’re thirsty. Where did this idea even come from?

According to Peter Attia, MD, the myth seems to have originated in a report by the National Research Council’s Food and Nutrition Board. They said that 1 ml of water per calorie of food is a “suitable allowance” per day for adults.

This roughly comes out to 8 glasses a day. But in this original report, they included in this allowance all the water that comes in food, which is a lot!

In any case, a thorough review of the scientific literature has found no good evidence to back up this recommendation. As Aaron E. Carroll, a physician and researcher put it in a New York Times article: drink when you’re thirsty.

Food Myth #3: An alkaline diet is the healthiest.

Science says: Not scientifically valid, although the foods considered to be alkaline are perfectly healthy. The “alkaline diet” is based on the idea that when foods we eat are metabolized, they leave behind waste that can be either acidic or alkaline.

Alkaline refers to one end of a range on which a liquid solution can be measured (the measurement is called pH and refers to certain chemical properties). Foods that are thought to leave behind alkaline waste are vegetables, fruits, nuts, and legumes, while foods that are thought to leave behind acidic waste are meat, dairy, and grains.

The idea behind the alkaline diet is that you can keep your body “alkaline” by eating these alkaline-producing foods and thus you’ll ward off disease. Not only is there no evidence for this, but the body necessarily tightly regulates the pH balance of our blood and it can’t be changed by eating alkaline foods. Another myth busted!

Food Myth #4: Ketogenic diets are the worst/best for your health.

Science says: Ketogenic diets are neither magical cure-alls nor heart-stopping death diets. High-quality research has shown ketogenic diets to reduce and in many cases eliminate epilepsy symptoms. Ketogenic diets have been shown effective for weight loss, but experts disagree on whether they are the best diet for this.

And while ketogenic diets have been shown to be effective in reversing type 2 diabetes, some experts question whether this happens independently of weight loss (in other words, any diet that produces weight loss will improve type 2 diabetes).

There is evidence in mice and some in humans that ketogenic diets may slow growth in some tumors, improve Alzheimer’s symptoms, and other neurological disorders. But these are preliminary studies and are a long way from being considered standard of care in oncology or neurology. On the other hand, ketogenic diets appear to be quite safe when overseen by a dietitian or other medical professional.

Food Myth #5: Organic food is clearly the healthiest option.

Science says: While organic farming and foods lead to reduced pesticide exposure, and have environmental, animal welfare, and producer-related economic benefits, there’s no expert agreement that these factors lead to a health benefit over conventional agriculture.

Skeptics of organic agriculture argue that because the health benefits of organic produce haven’t been demonstrated, the extra cost at the store may reduce the amount of fruit and vegetables people buy.

And some argue that the environmental benefit of reduced pesticides in organic crops is offset by the fact that these crops have lower yield-per-acre than conventional crops, and thus more land has to be planted, which is a net loss for the environment.

Unfortunately, there is no consensus view on whether organic foods lead to better health over conventional.

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