There are several nutrients and natural compounds that are uniquely effective for promoting healthy joints.

Glucosamine is a component of cartilage. When you take a glucosamine-containing supplement, the compound is incorporated into your cartilage molecules, which helps repair joints and reduce the pain that can result from overuse.

I recommend the glucosamine sulfate form (not glucosamine hydrochloride), because sulfate also promotes healthy joint function. The standard dose is 750 milligrams, 2 times daily, taken with or without food.

After 6 months, you may find that you don't need to take the supplement daily; at that point, you may choose to take it only when your joints feel like they need help.

Chondroitin sulfate also helps create, maintain and repair cartilage. One downside is that only 10 percent is absorbed.

To improve absorption, use the "low molecular weight" form of chondroitin. (Look for those words on the label.) The standard dose is 400 mg three times daily, or 1,200 in a single dose.

MSM is an abbreviation for methylsulfonylmethane, a sulfur-containing compound that gives your proteins a key building block needed for tissue repair. Research show that MSM, chondroitin and glucosamine work well together.

It is reasonable to take all 3 of these daily for the first 6 to 12 weeks after you begin the regimen. This will lay a solid nutritional foundation from which you can begin to maintain healthy joint function. After that, you can scale back to a lower dose.

For insurance, take a good general-purpose supplement. Dozens of other nutrients are also helpful to promoting healthy joint function — like B vitamins, vitamin C, vitamin E, boron, and zinc.