"The biggest deficiency in the American diet is not protein, it's fruits and vegetables," says Dr. Joel Kahn, a leading cardiologist and bestselling author, who himself adopted a plant-based diet 44 years ago. He tells his patients to get as close to a whole-food plant-based diet as they can. Perfection may not be the goal for everyone, he explains, but make moves toward it. A mostly plant-based diet full of healthy whole foods may be more attainable for most people than trying to achieve pure perfection.

We spoke to Dr. Kahn about his concerns over the misdirected American obsession with protein, the false hope that fake meat alternatives are healthy for us, and that if everyone just tried to eat the recommended 5 servings of fruits and vegetables a day, we would be way ahead of the current game. His view about what the best diet to aspire to, that is sustainable and healthy: What is now known as the "Green Mediterranean" diet, where most of the animal protein is replaced with plant sources like beans, whole grains, nuts, and seeds

Dr. Joel Kahn is a Clinical Professor of Medicine at Wayne State University School of Medicine and the bestselling author of The Whole Heart Solution, and he wants Americans to know that for their heart health and whole health, eating more plant-based foods in their most natural form is the goal. Skip the processed foods, whether it's in the form of a fake burger or anything else that doesn't grow from the ground.

Everyone in the medical community agrees on one thing: Processed food is poison

"I have friends in the paleo community and keto community and we all agree the big goal is to stop eating processed crap. If you want to be healthy and you are already eating the Mediterranean diet, I would rather see you move toward what we now call the 'Green Mediterranean' diet, which is more plant protein and less animal protein. But the one thing we all agree on is that processed food is poison," Dr. Kahn says.

He is also a realist, however, and unless someone has a heart condition (in which case he does proscribe a fully plant-based diet of whole foods with little or no oils), Dr. Kahn does try to point his patients in the direction of adopting a plant-based diet but tells them to do the best they can since it's likely not going to be 100 percent attainable. Instead, he nudges his patients who will listen to go as far as they possibly can toward eating a whole-food plant-based diet, since If they get close to it, he says, that's still a win. The goal is a "90-percent-plus whole food, plant-based, brightly-colored, largely organic diet, with a lot of spice and

The more plant-based you eat, the more benefits you get, health-wise.

"The more plant-based whole foods you eat, the better," Kahn says. 'If you go 75 percent plant-based in your approach, you'll get 75 percent of the benefits, and if you go 90 percent, you will get 90 percent of the health benefits. That is so much better than most of the American public since the vast majority of Americans eat fewer than the recommended 5 servings of fruits and vegetables a day." If you are in the 5 to 10 percent of Americans who hit that number or eat mostly or fully plant-based, Kahn tells us, then kudos to you, since eating a diet of mostly plant-based foods that are minimally processed lowers your risk of every major disease.

Eating a diet rich in whole plant-based foods and without animal products (especially processed meats, eggs, and dairy) means you lower your risk of heart disease, breast, prostate, and colon cancer, as well as Alzheimer's, studies show. But if you're like the vast majority of Americans, who are still not eating nearly enough whole fruit, fresh vegetables, whole grains, legumes like beans and lentils, nuts and seeds, the best thing to shoot for is not perfection but an improvement. Just start by eating more whole foods, and skip the junk.

First Dr. Kahn says, stay away from saturated fat, which is in animal products like butter, cheese meat, and dairy, and a new study that he has written about warns that eggs are equally bad for you, especially the yolks. If you want to be your healthiest, head to the produced aisle and load up on plants, and avoid processed foods. "If you can pronounce it, other than quinoa which most people don't know how to pronounce, you can eat it."

Everyone is asking the wrong questions when it comes to eating healthy

The usual question that Dr. Kahn gets asked by journalists is this: How bad are those fake burgers for you? He answers, but it's not really the core question that people should be asking. What is the best way to eat to be healthy? That's the vital question and how we get there may involve a stop on the way that includes a fake meat burger, but processed food is processed food, and the fact is that even plant-based processed food is terrible for you, Kahn explains.

"I always say: What were you eating instead? If you were going to have a sausage and cheese sandwich, then the Beyond or Impossible burger is better, certainly for the planet and animals, and perhaps for you. But if you are already eating a mostly whole-food, plant-based diet then it's the wrong direction to go in. Of course, if you want it occasionally, that is probably fine, but plant-based junk food is still junk food." I have friends in the paleo community and the keto community and we all agree the big goal is to stop eating processed crap.

Start by going vegan before 9. That means a plant-based breakfast

When someone starts out on a plant-based diet and wants to take it slowly, Kahn says, "Go vegan before 9," playing on the title of Mark Bittman's bestselling book Eat Vegan Before 6.

"What I mean by that is breakfast is a start. Have oatmeal and berries, with plant-based milk and nuts. Then add lunch to the plan, with a big salad or celery and carrots dipped in hummus. With changes that are consistent you'll see improvement. I had a patient try this and in a few weeks lost 9 pounds. Maybe your skin will improve. And if you want to do it fully, then there is a little nuance to it. Meaning you can see major benefits to going 90 to 100 percent whole food plant-based. It's really a good thing.

But if a patient tells me 'Doc I added one piece of salmon a week,' then if you are still eating well and if salmon is your guilty pleasure, then that is so far in the right direction. It is not the biggest deal-breaker ever."

If you have signs of heart disease, the message is to go plant-based, Dr. Kahn says

"I am seeing people–patients with stents and who need bypass who have serious heart disease–and that message might be a little tighter," he says. Then it's a matter of life and death. Stay off the meat and dairy and ditch the oils. Only eat whole plant-based foods to get rid of what is clogging arteries and causing more damage." But for the rest of the population, he asks: "What impact would there be to both animal and soil use if most Americans ate plant-based 75 percent of the time? It would be enormous. There is a big hairy goal of slowly moving the American diet toward a plant-based approach. That is the goal."

If everyone identified the enemy as processed crap, and we got away from government subsidies and recognized that the one goal is to start eating more whole plant-based foods, then that would have the greatest impact on our health and the planet. But I see plenty of people fill their freezer with plant-based junk and some of it is pretty tasty, but some of it is still junk. It has processed colors and flavors. So just because it's plant-based doesn't make it healthy. So the goal is to eat a whole food plant-based diet of simple meals with simple ingredients. That is the goal. Understand that vegans can still fall into the camp of junk food."

So when someone says to me: "'What do you think of Beyond meat burgers?' I ask them, Well are you eating baby back ribs covered in cheese? Then if that's the case, eat the Beyond, which is better for the cow and better for the planet. But it's not a quinoa black bean burger you can make at home for far less money that is much healthier for you." Of course, there are advantages to a plant-based burger option at restaurants, he adds, "If you are eating a whole plant-based diet and you are eating out with friends. then it's not a big deal to have it occasionally."

When it comes to diet, putting too much pressure on someone, even on yourself, is counterproductive, Dr. Kahn adds. If you want to think about where your food comes from and what is better for the environment, to reduce greenhouse gases and be healthier all around, then strive for a whole-food plant-based diet. But if you mess up occasionally, that is part of being human. Just do the best you can.

Dr. Kahn has been plant-based for 44 years. Here's what he eats in a day:

Breakfast: I start my day with a mankai (an ancient green) smoothie–high protein and green whole plant foods and choline in the morning with coffee and cacao powder, I'm not giving it up (coffee) far as that is concerned.

Lunch is a glass container of peas, beans, a lot of leftovers, and salads.

Dinner: Great vegan pizza with no fake cheese, just marinara, and vegetables. Or pasta and a lentil bolognese. Or Pad Thai, or other great foods that are remade as whole food and plant-based. You can make delicious foods vegan.

Snack: I love sweets so a small cookie or an apple or orange. One vegan cookie and shut it down. I drink tea all day long. One tea or another all day long.

Bottom Line: The Green Mediterranean diet with plant-based protein instead of animal protein is the best way to eat, with some time-restricted eating involved. I never eat after 7 p.m. By that time, I am brushing my teeth and say I am done.

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