Chapter 20
Lifestyle+ — 11
Figure 3.4. Relationship between red meat consumption, mortality, and environmental impact. Risk of mortality (upper panel) and risk of dying and relative environmental impact (middle panel). Adapted from Michael Clark et al., “Multiple health and environmental impacts of foods,” Proceedings of the National Academy of Sciences of the USA 116, no. 46 (November 2019): 23357–62, https://doi.org/10.1073/pnas.1906908116(lowerpanel); and “How much would giving up meat help the environment?,” Economist, November 15, 2019: https://www.economist.com/graphic-detail/2019/11/15/how-much-would-giving-up-meat-help-the-environment? (middle and lower panels).
What about plant-based meat alternatives? They are high in sodium, higher in saturated fats compared with high-protein plant sources including lentils and beans, and can be high in heme, a component of hemoglobin containing iron, as in the case of the Impossible Burger, which has been associated with more risk of type 2 diabetes. But there’s a lack of adequate studies. The bottom line is that the more red meat you eat, especially processed red meat, the less healthy you are likely to be. To date, the measured increase in cardiovascular and cancer risks are small but consistently point in the wrong direction.
Good Food
Many studies have confirmed the beneficial effects of “healthy eating.” Three large prospective studies with cumulatively more than 165,000 women and 43,000 men, followed up for thirty-two years, were consistent in showing a 15 to 20 percent lower cardiovascular risk linked to eating well. A lower risk of all-cause mortality was found in two of these prospective studies, with a dose relationship seen with cardiovascular, cancer, and neurodegenerative disease. For all these ailments, the higher the dose of healthy foods, the lower the risks. That’s good, but what exactly does healthy eating mean?
We know it includes fruits and vegetables; legumes, such as lentils and garbanzo beans; whole grains; nuts and seeds; healthy fats, such as olive oil and avocados; and fatty fish, such as salmon and tuna, rich in omega-3 fatty acids. Consumption of olive oil, per se, has been tied to about a 20 percent lower all-cause mortality, along with reduction of cardiovascular-, cancer-, and neurodegenerative-related deaths. Among more than ninety-two thousand participants followed for twenty-eight years, there was a significant lower risk of dementia: 28 percent less risk if a person consumed 7 grams (half a tablespoon) a day or more of olive oil compared with rare or no consumption. In aggregate, these foods provide good sources of dietary fiber, something we all tend to need more of. The recommendation for about 30 grams of fiber per day, adjusted by age, gender, and body size, is derived from a meta-analysis of 185 studies that showed people who consumed a high fiber diet had 31 percent less heart disease and 16 percent less type 2 diabetes or colon cancer. Fiber is the polar opposite of ultra-processed foods—it slows digestion, lessens glucose spikes, and helps reduce cholesterol. What is referred to as the Western diet, rich in ultra-processed foods, is pro-inflammatory and linked with metabolic dysfunction, cardiovascular disease, diabetes, and colon cancer. A randomized trial of a high fiber, “microbiome enhanced” diet compared to the Western diet with the same percentage of calories (isocaloric) for macronutrients led to less gut absorption of over one hundred calories per day (with some people over four hundred calories per day). Another way to put it: pooping calories instead of absorbing them!