Health Goals: How a Plant-Based Diet Can Keep You on Track

|Updated Jan 30, 2020
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Studies are a dime a dozen, and of course, anyone can twist a study to come up with whatever outcome they’re seeking. But doctors we spoke to agree that one thing is clear when it comes to improving health through diet: The direction of every recent study on diet and nutrition and health is that research favors eating more whole foods such as veggies, whole grains, fruits, nuts, seeds and legumes for your healthy living goals.

Still, need more evidence that shifting to a mostly plant-based diet is best for your health? Below, experts weigh in on some of the most convincing studies to either prevent, reverse or slow the progression of seven health woes.

1. Your goal:  Slim down

The study:  Comparing a vegetarian vs. conventional low-calory diabetic diet on the distribution of thigh fat, according to a randomized study of subjects with type 2 diabetes, published in The Journal of the American College of Nutrition (in2017).

What the study found:  Among adults with type 2 diabetes, half adopted a nearly vegan diet (they were allowed to eat one low-fat yogurt a day, although not  everybody ate this) while the other half of the study participants followed a conventional diabetes diet, which restricts portion size and limits carbs, thus requiring people to eat more animal products. Researchers measured changes at baseline, three months and six months, and by the end, although each group ate the same amount of calories, the nearly-vegan group lost almost twice as much weight – 13.67 pounds to be exact – versus the other group, who lost an average of 7.05 pounds. The plant-based eaters also lost more fat stored in the muscles.

The take-home:  When you eat mostly plants, you’ll increase your intake of fiber, especially if you’ve been following the standard American diet (which is extremely low in fiber). Simply put, high-fiber diets promote weight loss. Fiber also changes your gut microbiome, and the gut bacteria that feed on fiber have many metabolic benefits, weight loss included, says Hana Kahleova, M.D., Ph.D., study co-author and director of clinical research for the Physicians Committee for Responsible Medicine (PCRM).

2. Your goal: Lower your risk of heart disease and early death

The study:  A recent study of adults 40 and over reviewed the impact of a diet that emphasizes vegetables, fruits, nuts, whole grains, and minimizes the intake of trans fats, red meat and processed red meats, refined carbohydrates, and sweetened beverages is best. 2019 ACC/AHA Guidelines on the Primary Prevention of Cardiovascular Disease (Circulation, 2019)

What the study found:  Heart disease remains the top killer of men and women, but after four decades of decline, heart disease deaths rose again in 2015, a trend attributed to the obesity epidemic. Diet is certainly a driver of the rise in cardiovascular disease, as unhealthy eating has been linked with unhealthy hearts.

Dr. Kim Alan Williams, Chief of the Division of Cardiology at Rush University Medical Center in Chicago puts it this way: "Multiple studies have focused on the association of heart disease and mortality with dietary patterns –- specifically sugar, low-calorie sweeteners, high-carbohydrate diets, low-carbohydrate diets, refined grains, trans fat, saturated fat, sodium, red meat, and processed meat,” and found that the more plant-based you eat, the better.

The take-home:  Replacing animal protein with plants can help decrease your risk not only of heart disease but also early death of all causes. In one of the studies noted in this review, eating meat was associated with a 61 percent increase in mortality rate, versus if you replaced meat with nuts and seeds you lower your mortality rate by 40 percent.

In another study, comparing a diet of plant-based protein, to protein from animal sources found this: those who ate poultry and fish had a six percent higher mortality rate than those who ate plant-protein, and this jumped to 8 percent higher mortality risk if they included dairy, and a 12 percent higher mortality risk if they ate unprocessed meat, and 19 percent higher mortality risk if they ate eggs. But the highest mortality risk was found among those who ate processed and red meat, of 34 percent elevated risk.

On the flip side, those who ate more plant protein fared better:  For every three percent of energy replacement of animal protein with plant protein, there was a 10 percent reduction in the mortality rate.

Bottom line: The more you lean into a plant-based diet, the better.

3. Your goal:  Optimize heart health

The study:  Healthful and Unhealthful Plant-Based Diets and the Risk of Coronary Heart Disease in U.S. Adults (Journal of the American College of Cardiology, 2017)

What the study found:  Not only does this study support that plant-based diets are healthy and decrease rates of coronary artery events, it also reveals that there’s a range of plant-based diets, some healthier than others. It's easy to eat junk food that's devoid of animal product and call yourself vegan or plant-based. The best choices are whole-foods that are minimally processed, cooking with less oil, and avoiding added sugars and fats.

“Plant-based diets that are ‘healthful’ decrease event rates, but unhealthful plant-based diets have no benefit and can even increase risk,” says Dr. Monica Aggarwal, M.D., F.A.C.C., Director of Integrative Cardiology at the University of Florida, Gainesville.

The take-home:  Understand the difference between healthful and unhealthful plant-based diets and opt for the whole foods. Unhealthful plant-based diets include refined carbohydrates and simple sugars like cookies, French fries, potato chips, non-dairy ice creams and sugary sodas. Meanwhile, a healthful plant-based diet focuses on fruits and vegetables, whole grains, beans and lentils, nuts and seeds, and spices.

4. Your goal:  Stave off breast cancer

The study: Low-fat dietary pattern and long-term breast cancer incidence and mortality: The Women’s Health Initiative randomized clinical trial (American Society of Clinical Oncology annual meeting, 2019)

What the study found:  The research supports a strong link between diet and breast cancer. However, this study connected diet and cancer occurrence among nearly 50,000 postmenopausal women, who were followed for over two decades. Those who ate a lower-fat diet and concentrated their diet on more fruits, vegetables, and grains had a 21 percent lower chance of breast cancer over the decades. Three things make this particularly significant, says Dr. William Li, physician, scientist and best-selling author of Eat to Beat Disease: The length of the study, the fact that patients were enrolled from 40 different medical centers throughout the United States, and the fact that minorities were included in the cohort.

The take-home:  Add more fruits, vegetables and grains (choose whole grains over refined carbs) to your diet. “Plant-based foods contain natural chemicals that are bioactive that can help starve cancerous tumors, kill cancer stem cells and protect your DNA from damage,” Li says. "Fiber, which is found only in plants, will also improve your gut microbiome, boosting your immune system’s ability to find and destroy cancer cells." At the same time, lower the overall fat in your diet.

In addition to swapping saturated fats for polyunsaturated fats found in healthy plant oils like olive oil, reduce the amount of red meat you eat, another source of unhealthy fat. Red meat has also been shown to change your gut microbiome in ways that promote inflammation, which is associated with fueling cancer development, he adds.

5. Your goal:  Decrease symptoms of rheumatoid arthritis

The study:  Nutrition Interventions in Rheumatoid Arthritis: The Potential Use of Plant-Based Diets. A Review (Frontiers in Nutrition, 2019)

What the study found:  A surprising one percent of the world’s population suffers from this debilitating autoimmune disorder. While drugs have been the primary line of defense against RA, this study, one of the first of its kind, suggests that a simple swap to a whole-food, plant-based diet can not only help symptoms like pain and swelling improve but showed in some cases the symptoms disappear. “Animal foods promote inflammation, so when you remove the animal foods, you reduce the inflammation in as a little as two to three weeks,” says study co-author and researcher Hana Kahleova.

The take-home:  Eating mostly plants is the way to go. The one caveat? “There are some foods in the plant kingdom that can still trigger inflammation in some individuals,” Kahleova says. If you’re struggling after switching to a plant-only diet, you may need to go through an elimination diet, excluding other potential triggers like beans, citrus fruit, onions, soy, and nuts.

6. Your goal: Get elevated cholesterol in check

The study:  Examine the association between plant-based diets and elevated levels of plasma lipids (Nutrition Reviews, 2017)

What the study found: Researchers from the Physicians Committee for Responsible Medicine compared vegetarian and vegan diets with omnivorous diets to determine which might lead to better (lower) cholesterol levels. So which one won? Although the vegetarian diet did lower total cholesterol, and even LDL (aka bad) cholesterol, a whole-food plant-based vegan diet had the most benefit on LDL, and the measure of lipid levels in the blood.

The take-home:  If you have elevated LDL, which can be a precursor to heart disease and clogged arteries (which may also lead to stroke and other causes of early death) choose a more plant-based diet. Researchers say that switching to a plant-based diet can help you lose weight and when you cut your saturated fat intake you will likely see cholesterol go down.

7. Your goal: Fight or prevent diabetes

The study:  The connection between vegetarian diets and the risk of diabetes (Current Diabetes Reports, 2018)

What the study found:  This review of studies concluded that “a vegetarian diet characterized by whole plant foods has the most benefits for diabetes prevention and management.”

Of note? In one study the researches highlighted, vegans had the lowest rates of diabetes versus Lacto-Ovo vegetarians, pescatarians, semi-vegetarians, and non-vegetarians. Vegan diets also showed the most benefits in reducing blood sugar levels -- called fasting plasma glucose levels -- in people with diabetes and other complications like heart disease.

The take-home:  Most people think diabetes is all about carbohydrates and sugar, but that’s not the full picture. The real culprit when trying to lower diabetes appears to be fat, according to this new research. “When you eat a high-fat diet, you tend to store fat in the body, which gets into the cells,” says Pam Popper, Ph.D., N.D., President of Wellness Forum Health in Columbus, Ohio. As a result, that fat blocks your body’s insulin signaling response. Think of insulin as a key that lets blood sugar or glucose enter your cells. When too much fat is present in the blood, insulin can’t do its job, so that glucose builds up in your blood, causing blood sugar levels to increase and making you insulin-resistant.

Yet when you switch to a healthy plant-based diet (think whole grains, fruits, vegetables, nuts, and legumes and not a lot of oils) that’s naturally low in fat, “the weight falls off your body, and the fat pours out of your cells in a short time, allowing you to become insulin sensitive,” so you lose weight, Popper adds.

Whatever your health woes or goals, these studies all suggest that the best way to lower inflammation and lose weight for the long term is a whole-food plant-based diet, low in oils and minimally processed foods. The Beet welcomes your tips, comments and helpful hacks for how to "just add plants" to your plate to be your healthiest and eat delicious food, too.