In fact, vegan InsideTracker users have significantly lower levels of ferritin than those who eat animal products regularly. This often results in lower iron stores and levels. Non-heme iron (the form found in plant sources), on the other hand, is in a more difficult structure for our bodies to absorb. 13 This is because heme iron is perfectly structured for our bodies to absorb and use, directly influencing our red blood cell and iron biomarkers. People who eat animal products with high concentrations of heme iron (the form of iron found in animal sources), like meat and seafood, have significantly higher levels of hemoglobin and hematocrit than those who exclusively get their iron from plant sources. Good plant-based sources of protein include tofu, lentils, and pumpkin seeds. Otherwise, be sure to monitor your protein intake and ensure you're hitting your daily needs (which depend on things like sex, age, and activity level). If you follow a vegan diet but are willing to experiment, try supplementing your diet with animal products and monitor your blood levels of SHBG and testosterone over time for any changes. These patterns do appear to hold true for InsideTracker users – vegans have both lower testosterone and higher SHBG levels than non-vegan users. Testosterone metabolism is complex and levels can be unoptimized for a variety of reasons, however, high SHBG is not the sole culprit. However, given the information above, SHBG prevents bound testosterone from leaving the body. Since SHBG binds testosterone, high levels may create a false pretense of low testosterone levels. Additionally, SHBG prevents sex hormones from being cleared from the bloodstream, acting as a pool of reserved hormones that can be tapped into when levels become low. SHBG levels tend to increase in parallel with testosterone levels, given it's responsible for regulating sex hormone levels. SHBG safely transports sex hormones throughout the bloodstream and regulates their levels within the body. This relationship holds true for women, too vegan women have significantly higher levels than their meat-eating ones. Men who follow a vegan diet have significantly high Sex Hormone Binding Globulin (SHBG) than those who eat meat. 7 So if your glucose or A1c levels are above optimal, consider reducing your red meat intake. This might not seem intuitive at first – glucose is a carbohydrate, and animal products mostly contain fat and protein, so where’s the overlap? Well, the specific type of iron found in animal foods (more on that in a minute) may interrupt glucose metabolism. The same pattern has been found in multiple studies (the same goes for hemoglobin A1c, too!). While the difference doesn’t appear to be huge in the chart below, vegan InsideTracker users do have significantly lower blood glucose levels than non-vegans. 2-5 If you’re concerned with your heart health or have trouble controlling your cholesterol levels, consider reducing your animal product intake.
In a more general sense, massive studies of thousands of people agree that vegan diets are associated with a lower risk of cardiovascular disease than omnivorous ones. And this checks out – a summary of multiple trials found that vegetarian diets result in lower LDL levels than those which include meat.
InsideTracker users who identify as vegan (reported never or rarely eating animal products) have considerably lower LDL cholesterol than those who do not (reported consuming animal products once a month or more). Here are a few areas that show distinct differences between the two groups.
But the question remains: where do animal products fit into the puzzle? Does meat and cheese belong in what we consider a "healthy" diet, or is vegan truly the only way to go when it comes to physical health? We compared blood results from our vegan and non-vegan users to see who's really healthier. We've been taught what a general, baseline healthy diet is: lots of plants, sweet treats rarely, healthy fats and fiber, and a few other buzzwords.