There’s no “one size fits all” when it comes to the ideal diet. Everyone is different. Some people fare best on a meat-based diet, while others thrive on a plant-based approach. The only way to truly know what works best for you is to try both for a period of time and see how you feel.

If you want to speed up the process, however, here are two tests from the book Metabolic Man: Ten Thousand Years from Eden by Charles Wharton:

A) Niacin Test
Swallow 50 mg of niacin on an empty stomach, wait 30 minutes, and observe the response:

• If your skin turns red and feels very hot and itchy – You likely have a meat-eating metabolism
• If you only feel warmer and have a little facial color – You may require a balanced diet
• If nothing happens – You may be more suited to a vegetarian diet

B) Ascorbic Acid Test
Take 8 grams of ascorbic acid daily for 3 days and observe the effect:

• If you feel depressed, lethargic, exhausted, and irritable – You’re likely a carnivore
• If nothing happens – A balanced diet may be best
• If you feel better – You may be more suited to a vegetarian diet

These simple tests can help point you toward the dietary approach that works best for you—at least for now. It’s a good idea to retest periodically, as your needs may change over time.