Start with the hs-CRP (high-sensitivity C-reactive protein) test. It measures the amount of C-reactive protein in your blood, which in turn is a marker for systemic inflammation. Ideally, you’d like it to be 1.0 or under, as inflammation is a promoter of just about every degenerative disease on the planet.
I’d also want a test for homocysteine, a nasty little inflammatory metabolite of methione, which can build up in the blood and increase the risk for dementia.
Most functional medicine physicians ask for the cholesterol particle test (which is a much more detailed and information-heavy test than the standard HDL/LDL blood test). My personal functional medicine doc also does a vitamin D test (the 25-hydroxy vitamin D test) and a fasting insulin (which is a really good measure of how you metabolize carbohydrates), as well as all the standard hormone tests (testosterone, thyroid, estradiol, etc).
A test you can do at home (for free) is your waist-hip ratio, a great predictor of health and quite independent of actual weight because it tells you about where you store your fat. Research has shown that carrying fat around your middle is far worse than carrying it around your hips. According to the World Health Organization, the ideal waist-to-hip ratio for women is 0.85 centimeters or below, and for men it’s 0.9 centimeters or below.
Here’s how: Measure your hips at their widest place, measure your waist at its narrowest place, then divide the waist by the hip measurement. You can also do a plain old-fashioned waist measurement. While different health organizations specify slightly different numbers for the ideal waist circumference, most doctors and health experts, including myself, agree that the healthiest category is 35 inches or less for women and 40 inches or less for men.
Finally, don’t devalue the importance of your own experience. To me, the greatest marker for “doing better” is energy. If you’ve got it, and you’re feeling good consistently, that’s probably a better metric than all the lab tests in the world.