The Plant Predominant Diet (PPD) is 90-95% plant-based with the addition of small quantities of fish or animal products such as dairy, eggs, and meat. The main players in a plant-based diet include nutrient dense vegetables, fruit, seeds, nuts, legumes, lentils, tubers, sea vegetables and whole grains. Ideally, a plant predominant based diet focuses on whole foods while excluding processed foods such as vegetable oils, refined sugar, white flour, packaged, and fast food.
Why should I eat more plants?
In a nutritional update for physicians, a plant-based diet is now being recommended as a cost-effective, low-risk intervention that will improve health outcomes. Plant predominant diets are naturally lower in unhealthy fat, cholesterol, salt, and sugar. Research shows that switching to a plant-based diet can reduce the incidence of obesity, diabetes, hypertension, hyperlipidemia, and heart disease! Those who eat less meat and more vegetables have lower body mass index, lower systolic blood pressure, lower serum LDL, and healthier blood vessel walls.
Do you have to completely give up meat to benefit from eating plant-based foods?
When the microbiota in the intestines metabolize nutrients in red meat (L-carnitine) and dairy, seafood, and eggs (phosphatidylcholine), a pro-atherosclerotic metabolite called trimethylamine-N-oxide (TMAO) is produced. This toxin causes the arteries to harden and narrow, increasing the risk for cardiovascular disease. Research shows that while animal product consumption increases TMAO, the consumption of polyphenols from fresh fruits and vegetables is associated with decreased TMAO. Once your microbiome shifts its population to the more plant loving strains (by eating a predominately plant-based diet), the occasional consumption of animal products will not convert phosphatidylcholine or L-carnitine to TMAO.
This means that if you eat a Plant Predominant Diet like the Mediterranean style diet and occasionally eat animal foods, you should still see a protective effect against cardiovascular disease. This is related to how your microbiome adapts to its environment (see more below)! If you do consume animal protein or fish, treat it as more of a condiment and don’t consume it at every meal or even every day. Choose only grass-fed beef which is higher in omega-3, wild-caught seafood, organic dairy, and pastured raised organic poultry/eggs.
What if I eat a 100% plant-based diet, but it contains processed foods?
The Devil is always in the details. A French-fried potato is a vegetable and fructose is derived from fruit, right? Unfortunately, a less healthy plant-based diet is still associated with a higher cardiovascular disease risk just as with a predominately animal-based diet. The healthier version of a plant-based diet includes whole grains, fruits/vegetables, nuts/legumes, plant oils, and tea/coffee while the less-healthy version includes juices/sweetened beverages, refined grains, potatoes/fries, and sweets. Start transitioning to a whole foods diet by slowly increasing your consumption of fruits and vegetables with every meal.
How can I get enough protein from plants?
Beans and lentils are a staple of a plant-based diet. They have been shown to contribute to weight loss since they are low glycemic, high fiber, and high protein which leads to better blood sugar regulation and an increased feeling of fullness. While only a few plant foods contain a complete protein source, if you eat a wide variety of plant foods, you will generally consume all the essential amino acids you need. Stick to the whole foods sources, like quinoa, and stay away from the heavily processed soy-based meat substitutes or isolates.
While eating too little protein is a problem, the opposite can also have negative health consequences. The Standard American Diet tends to be excessive in animal protein. The overconsumption of protein causes excess free branch chain amino acids which chronically activates the mammalian target of rapamycin (mTOR) pathway. mTOR is a signaling protein that senses amino acid concentrations, and increased levels are associated with insulin resistance, accelerated aging, cancer, and chronic disease. The amino acid Leucine seems to have the most dramatic effect on mTOR, and Leucine is found mainly in animal foods like eggs, dairy, red meat, chicken, and fish.
The bottom line is to consume enough protein to meet your bodily needs, which can vary by activity level, if pregnant or breastfeeding, and by age. Focus on plant-based proteins and if desired, consume meat and fish a few times per week.
Will I get all the nutrients I need on a plant-based diet?
There are certain nutrients (vitamin B-12, iron, calcium, essential fatty acids, vitamin D, and iodine) that should be monitored on a plant-based diet, but eating a varied diet with 7-9 cups of fruits and vegetables per day, dark leafy greens, nuts and seeds, legumes, and sea vegetables is a good foundation. A plant-predominant diet should be well planned out to include all of these foods plus bio-active foods like ginger, turmeric, green tea, onions, and cruciferous vegetables. The PPD is naturally rich in fiber and polyphenols which help reduce and prevent chronic inflammation. If not consuming any animal protein, vitamin B-12 should be supplemented since a vitamin B-12 deficiency is serious and can lead to macrocytic anemia and irreversible nerve damage.
Why Would I Want a Plant-based Microbiome?
We truly are what we eat! A plant predominant diet is rich in fiber and this cultivates the fiber-eating bacteria in our gut which are symbiotic to us and in turn increase anti-inflammatory and anti-cancer short-chain fatty acids. Even after just one month on a plant-based diet, the ratio of beneficial to pathogenic bacteria improved and gut inflammation decreased. An animal-based diet is associated with pathobionts, which are disease-causing bacteria associated with inflammatory bowel disease, abscesses, appendicitis, low-grade inflammation as well as impaired glucose tolerance and lipid metabolism. The microbiota adapts to their environment, which is determined by the food we eat!
Do you want to live past 100? What do centenarians eat?
There are five geographic areas that hold the world’s longest living people often called Blue Zones. While diet is definitely not the only factor in their longevity, the dietary patterns are similar in all five of the main Blue Zones (hint, hint). Plus, they also get ample vitamin D from the sun!
Let’s take a look at the dietary patterns of these five areas.
Sardinia, Italy: whole-grain bread, beans, garden vegetables, fruits, some eat mastic oil, pecorino cheese from grass-fed sheep (high in omega-3), and meat which is generally consumed on Sunday or on special occasions.
Okinawa, Japan: stir-fried vegetables, sweet potatoes, tofu, goya, miso soup, mugwort, ginger, turmeric, and small amounts of pork for ceremonial occasions.
Loma Linda, California (Seventh-day Adventists): no alcohol, nuts, fruits, vegetables, avocados, legumes, salmon, whole grain bread, oatmeal, meat as a side dish for some. Many follow a vegetarian diet, and they eat a larger breakfast and smaller dinner.
Nicoya Peninsula, Costa Rica: homemade corn tortillas (soaked in lime), black beans, pejibajes, plantains, bananas, papaya, squash, and rice.
Ikaria, Greece: Mediterranean style diet including fruits, vegetables, whole grains, beans, potatoes, antioxidant-rich herbs (rosemary, sage, oregano), grass-fed goat’s milk, and olive oil plus red wine. Ikarians are almost entirely free of dementia and 1 in 3 make it to their 90s!
According to Dan Buettner, the author of The Blue Zone Solutions, the general dietary guidelines for longevity is predominately plant-based. Fish may be consumed 2-3 times per week, but it should be uncontaminated, which may be hard to find. Dairy should be minimized and ideally come from sheep (pecorino) or goat (feta). Eggs should be limited to 3 per week. One cup of beans (including soy) should be eaten daily and can be spread throughout the day. Keep sugar consumption to less than 7 teaspoons per day (28 grams) and use raw honey to sweeten, if needed. Eat a handful of nuts daily (ideally raw and unsalted). If eating bread, limit to two slices of whole grain or sourdough (from live cultures). Drink mostly water or unsweetened teas and coffee. Enjoy moderate consumption of wine with friends or with meals.
Which Supplements Should I Consider on a Predominately Plant-Based Diet?
While everyone has unique nutritional needs based on their food intake and other factors, there are several supplements that may be beneficial on a plant-based diet. Those are vitamin B-12, algae-based omega-3 (DHA), multivitamin/mineral, calcium, iron, and probiotics. Supplement requirements should be addressed with a nutritionist in order to determine need and optimal dose for your specific health considerations.
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