Thanks to popular wisdom, we tend to consider animal protein our dietary MVP – it’s associated with building muscle, and high-animal protein weight loss diets are still popular. In contrast, plant protein from vegetables, legumes, nuts and seeds is considered a “second string” source. But as usual, popular wisdom only gets part of the story right. When it comes to protecting your cardiovascular health, it is the source of your protein that matters most.
Many studies have demonstrated that plant protein is beneficial – and animal protein is harmful – regarding outcomes such as cardiovascular disease, cancer, and death from all causes. But new data, gathered by the Adventist Health Study 2, takes a more nuanced look at exactly which types of plant and animal proteins have the greatest impact on your risk of heart disease. Researchers decided to ask which protein-containing foods in particular contribute to increasing or decreasing cardiovascular risk. It will come as no surprise to Nutritarians that nuts and seeds emerged as the most beneficial source of this vital nutrient.
All protein is not equal
In this new study, researchers focused on the specific sources of the subjects’ protein intake. A total of 81,337 participants were asked about their usual intake of these foods during the previous year, and then they were followed for 6-12 years. Data was analyzed to determine the percentage of total protein that came from these animal and plant sources.
Of all the plant and animal protein sources analyzed, risk of cardiovascular deaths steadily climbed with higher consumption of meat protein, and steadily fell with greater consumption of protein from nuts and seeds.
In the groups with the highest meat intake, risk was about 60 percent higher than in the group with the lowest intake. In the group with the highest intake of nuts and seeds, the cardiovascular risk was about 40 percent lower compared to the group with the lowest intake of nuts and seeds.1
These results are consistent with previous research that has compared nuts to meat as a major calorie source.2 Plus, there have now been numerous studies linking higher nut intake to longevity.3
Why is meat so harmful to the cardiovascular system?
In addition to cardiovascular disease, diets high in animal protein also promote cancer. Animal protein, which has a higher biological value (compared to plant protein) because of its greater essential amino acid content, is absorbed and utilized quickly by the body. This raises IGF-1 to dangerous levels, which promotes the growth of tumors and enhances fat storage.12-15
Why are nut and seeds so protective?
In addition to their cardiovascular benefits, nuts also facilitate the absorption of vegetable-derived phytochemicals, which increases the anti-oxidant potential and the protective function of immune system cells.24 Calories from nuts and seeds are absorbed very slowly, which means that the body is more likely to use them for energy rather than storage. IGF-1 levels that are too high or too low are detrimental to health, and the major determinant of IGF-1 levels is essential amino acid intake.14,27
As protein and fat sources, nuts and seeds are the clear winner over animal products. Nuts and seeds are crucial for cardiovascular health and longevity. Now that’s the kind of wisdom that deserves to be popular.
Now that you know why your protein should come from the dirt rather than off the hoof, here are a few easy ways to improve the quality of your diet. And if you have any great tips that work for you, please share them in the comments section!