People with severe, persistent, or hard-to-treat acne should consider getting their vitamin levels checked. Many people with adult acne are deficient in zinc, vitamin A, vitamin D3, omega 3 and even calcium. All are deeply connected with the body's inflammatory response and when levels dip too low, can trigger inflammation. Bringing those levels back up will help calm inflammation, and with the first 4, there's wiggle room to take a little extra. Zinc, vitamin A, D3, and omega 3 have powerful anti-inflammatory properties and work synergistically to balance inflammation.

Zinc...30-50 mgs per day are safe amounts to take, but anything over 100 mgs can be toxic, and can also dry out your skin too much. 50 mgs per day would be good for oil control. Eating 3-4 oysters are a great way to get your zinc!

Vitamin A...10,000 IU per day is optimal. Eating 2-3 carrots a day fulfills that requirement. Cod liver oil is another great source of vitamin A.

D3...RDA says 400 IU (assuming they're getting most of their intake from the sun) but most people actually need to supplement with 1000 IU D3 or more depending on where you live and how close you are to the equator where the sun is the closest to the earth, per recent studies. 2,000-3,000 IU is fine for most people. Your body will store excess and save for wintertime. Anything over 5,000 IU requires doctor supervision. 10,000 - 50,000 IU is in the toxic range depending on the individual.

Omega 3...to be therapeutic for skin, you'll want to find a fish oil that can supply you with 1000 mgs EPA omega 3 per day. This may mean taking 2-3 capsules. Look for the most potent and concentrated formulas you can find so you're taking the fewest capsules.

Calcium...This one is tricky, as too much can overstimulate hormone production, which can aggravate acne. And too little can trigger an inflammatory response. So be sure you're getting 100% RDA in your supplement or your food, but don't overdo it.