Q: I’m 85 pounds overweight and have type 2 diabetes, so I thought bariatric surgery might be the answer.

But I started doing research and got confused. Is lap-band surgery as effective against diabetes as gastric bypass, and what is gastric sleeve surgery?

PHIL M., UPTON, MA.

A: Let’s clear this up for you. There are three types of bariatric surgery: gastric bypass, gastric sleeve and gastric band (or lap-band) surgery. The lap-band procedure has fallen out of favor because the band can slip, causing complications. So we’re only going to look at the first two types.

Gastric bypass surgery staples your stomach to make it smaller and bypasses part of the small intestine. After a year, 67 percent of people on insulin go med-free and 96 percent of those on oral meds top taking them.

Gastric sleeve surgery, or sleeve gastrectomy, removes about 85 percent of the stomach, so that it takes the shape of a tube or sleeve. There’s less data on this procedure, but it does take longer to lose weight with this than with gastric bypass.

These procedures also are known to cure sleep apnea and gastric reflux disease. They also may reduce high blood pressure and cholesterol levels.

However, gastric bypass and gastric sleeve surgery may lead to decreased bone density (although the National Institutes of Health doesn’t think there’s conclusive evidence on this).

These surgeries reduce the nutrients you take into your gut. It’s important to eat right; take multivitamins and vitamin B-12; drink lots of water; go easy on alcohol, caffeine, sodas and acidic foods; and get plenty of exercise.

Bariatric surgery is a major advance in treating type 2 diabetes, if you’re overweight and can’t control your blood sugar levels. Just make sure you go to an experienced center, ask to see info on its results, and ask for references from post-op patients to see what their experience has been.