Dr. Jain: This is so helpful, Dr Gardner. I know that many clinicians, including myself, will find this very helpful, including when we talk to our patients and counsel them on their requirements. Thanks for sharing that.
Final question for you. We know people who are on either side of the extreme: either completely plant based or completely animal based. For a majority of us that have some kind of a happy medium, what would your suggestions be as far as the macronutrient distribution that you would recommend from a mixed animal- and plant-based diet? What would be the ideal recommendations here?
Dr. Gardner: We did a huge weight loss study with people with prediabetes. It was as low in carbs as people could go and as low in fat as people could go. That didn’t end up being the ketogenic level or the low-fat, vegan level. That ended up being much more moderate.
We found that people were successful either on low carb or low fat. Interestingly, on both diets, protein was very similar. Let’s not get into that since we just did a lot of protein. The key was a healthy low carb or a healthy low fat. I actually think we have a lot of wiggle room there. Let me build on what you said just a moment ago.
I really don’t think you need to be vegan to be healthy. We prefer the term whole food, plant based. If you’re getting 70% or 80% of your food from plants, you’re fine. If you really want to get the last 5%, 10%, or 15% all from plants, the additional benefit is not going to be large. You might want to do that for the environment or animal rights and welfare, but from a health perspective, a whole-food, plant-based diet leaves room for some yogurt, fish, and maybe some eggs for breakfast instead of those silly high-carb breakfasts that most Americans eat.
I will say that animal foods have no fiber. Given what a hot topic the microbiome is these days, the higher and higher you get in animal food, it’s going to be really hard to get antioxidants, most of which are in plants, and very hard to get enough fiber, which is good for the microbiome.
That’s why I tend to follow along the lines of a whole-food, plant-based diet that leaves some room for meat and animal-sourced foods, which you could leave out and be fine. I wouldn’t go in the opposite direction to the all-animal side.
Dr. Jain: That was awesome. Thank you so much, Dr Gardner. Final pearl of wisdom here. When clinicians like us see patients with diabetes, what should be the final take-home message that we can counsel our patients about?
Dr. Gardner: That’s a great question. I don’t think it’s really so much animal or plants; it’s actually type of carbohydrate. There’s a great paper out of JAMA in 2019 or 2020 by Shan and colleagues. They looked at the proportion of calories from proteins, carbs, and fats over about 20 years, and they looked at the subtypes.
Very interestingly, protein from animal foods is about 10% of calories; from plants, about 5%; mono-, poly-, and saturated fats are all about 10% of calories; and high-quality carbohydrates are about 10% of calories. What’s left is 40% of calories from crappy carbohydrates. We eat so many calories from added sugars and refined grains, and those are plant-based. Added sugars and refined grains are plant-based.
In terms of a lower-carbohydrate diet, there is an immense amount of room for cutting back on that 40%. What would you do with that? Would you eat more animal food? Would you eat more plant food? This is where I think we have a large amount of wiggle room. If the patients could get rid of all or most of that 40%, they could pick some eggs, yogurt, fish, and some high-fat foods. They could pick avocados, nuts, seeds, and olive oil or they could have more broccoli, chickpeas, tempeh, and tofu.
There really is a large amount of wiggle room. The key – can we please get rid of the elephant in the room, which is plant food – is all that added sugar and refined grain.
Dr. Jain is an endocrinologist and clinical instructor University of British Columbia, Vancouver. Dr. Gardner is a professor of medicine at Stanford (Calif.) University. Dr. Jain reported numerous conflicts of interest with various companies; Dr. Gardner reported receiving research funding from Beyond Meat.
A version of this article first appeared on Medscape.com.