Suck in and measure your waist at your belly button. It should ideally be less than half your height—about 40 inches for men, 37 inches for women.
The ideal blood pressure is approximately 115 over 75. "If the systolic or first number is 140 or above or if your diastolic or second number is 90 or more, alert your doctor," he says.
This ratio is the third number you need to know. "You want your LDL, or lousy cholesterol, to be less than 100," Dr. Oz says. "You want your HDL, or healthy cholesterol, to be greater than 40."
Resting Heart Rate
Take your pulse when you get out of bed in the morning and strive to get it as close to 60 as possible.
A simple finger stick can help you discover your blood sugar levels. "When your blood sugar is high, it's like if I take [a] glass and crack it on the ground and take the glass shards and scrape the insides of your arteries," he says. "That's what those sugar molecules do inside of you."
You should also know your vitamin D levels—more Americans are deficient in vitamin D than any other vitamin. Vitamin D can help a person prevent cancer, heart disease, multiple sclerosis, diabetes, autoimmune ailments and thyroid problems. You can get enough through 15 minutes a day of sun exposure during the summer or a daily vitamin D supplement with 1,000 units.
This is a way to tell if your body is full of inflammation and irritation. "If you've got gingivitis, prostatitis, vaginitis—if you've got any of these inflammations in your gut—they can elevate the C-reactive protein," he says. "C-reactive protein tells us how much of a battleground there is inside of you."
Thyroid Stimulating Hormone, or TSH
As Oprah learned the hard way in 2007. "If you have unexplained weight gain. If your hair has changed. If you don't have the get up and go. If your libido's off, the number one thing that we check is thyroid stimulating hormone," Dr. Oz says. "It tells us whether your thyroid gland is functioning normally."