Pros and Cons of Raw Food Diets

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

Is it better to eat our vegetables raw or cooked? If you’re thinking raw, you’re right! But if you guessed cooked, you’re also right! A number of nutrients, like vitamin C, are partially destroyed by cooking. On the other hand, some nutrients, like lycopene in tomatoes, become more absorbable upon cooking. So, I advocate eating a combination of cooked and raw foods.

Check out this study on long-term raw foodists. This study was done in Europe, so the “average Western diet” here wasn’t terrible––about four servings of fruits and vegetables a day; versus a better so-called “wholesome nutrition” diet of seven daily servings of fruits and veggies, both raw and cooked; versus a raw food diet, in which they ate, on average, a whopping 17 servings of fruits and veggies a day. This led them to have about three times the beta carotene intake compared to the “average” eaters. But that’s intake. How much of it actually got into their bloodstreams? Blood beta carotene is considered to be a surrogate marker for fruit and vegetable consumption. Some researchers even suggest if you “tell me what your blood beta carotene level is, I will tell you what your health risk is!” 

So, who had the most beta carotene in their bodies? Those eating four servings a day, seven, or 17? It was the middle group—the seven daily servings group—because cooking can boost the absorption of phytonutrients like beta carotene. For example, you get more beta carotene in your bloodstream eating cooked carrots than you do eating the same amount of raw carrots. The raw foodists were eating 17 servings a day, and basically had the same amount of this phytonutrient reaching their internal organs as those on the standard diet getting four measly daily servings!

Raw diets can be better than junky vegan diets because they’re free of processed foods like potato chips and sugary drinks. I couldn’t find any good evidence raw diets are superior to whole food plant-based diets, though. A dietary survey of 141 so-called Hallelujah vegetarians, following a mostly raw, pure vegetarian diet, found their raw food diets were deficient in energy, protein, vitamins B12 and D, calcium, selenium, and zinc. A more recent survey of strict raw food eaters disturbingly found only about half were supplementing with vitamin B12, and were suffering the consequences: elevated levels of the toxic metabolite homocysteine.

Most eating the average Western diet are getting way too many calories, but strict raw-foodists may not get enough. Being underweight, along with nutritional deficiencies, can cause women to lose their period, and could contribute to osteoporosis. Those eating 100 percent raw can become too skinny. And as many as half may stop having their period. Does this actually have an effect on bone mass? Raw foodists had significantly lower bone mineral density throughout their entire skeleton, and specifically in their spine and hips.

There are a number of seriously flawed myths that circulate within the raw foods community, like we need to consume live plant enzymes, which are deactivated by cooking. Well, they’re deactivated by our stomach acid too. And since we’re not plants, we have no need for plant enzymes. Our body makes all the enzymes we need to function from the protein we eat.

If, for whatever reason, you want to eat 100 percent raw, first, you must take a B12 supplement so you don’t get other nutrient deficiencies. Study Davis and Melina’s comprehensive guide on the subject. Also, a diet based on modern cultivated fruits is not nutritionally adequate. They’re a pale shadow of the wild fruits eaten by our ape ancestors. Make sure you rinse the natural acids off your teeth after eating sour fruits and beverages so you don’t erode your dental enamel. And also make sure you sufficiently chew your food so you don’t block your digestive tract. In fact, we explicitly recommend against raw food diets for young children, as they just don’t have the stomach capacity to get adequate nutrition.

Although an all-raw food diet can be healthy (this raw triple-ironman showed no signs of dietary deficiencies or impaired health), there is no reliable evidence to suggest that it’s more healthful than a diet of whole plant foods—cooked or not.

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Motion graphics by Avo Media

• beta carotene
• calcium
• carrots
• fruit
• lycopene
• osteoporosis
• Plant-Based Diets
• raw food
• selenium
• tomatoes
• vegetables
• vitamin B12
• vitamin C
• vitamin D
• zinc