WALNUT CREEK, Calif. — The signs of summer are everywhere. Tan, toned arms. Skimpy clothes. And sopping wet armpits.

We spend the majority of the year yearning for heat, and once it arrives, we suffer in constricting office attire as triple-digit temperatures turn even a leisurely, lunchtime stroll into a sweat fest.

But John Hanken knows how to deal with it. Hanken, who works and lives in Walnut Creek, Calif., usually eats at the La Salsa in his office building. When he leaves, he's got a sweat-proof system.

"Walk slowly," Hanken says. "Never go without an undershirt. It keeps you cool in the summer and warm in the winter." He also has a diplomatic take on antiperspirant and deodorant.

"Man, you've just got to wear that stuff," he says. "Wear it for your co-workers."

Sweating, the body's built-in air conditioner, is natural, whether caused by heat, stress, genetic or underlying medical conditions such as an elevated thyroid level.

"A lot of people have a little sweating," says Dr. David Bank, a New York dermatologist and director of the Center for Dermatology, Cosmetic and Laser Surgery. "The difference is some people whose lives are affected because they are gushing rivers and geysers."

Over-the-counter antiperspirants are the first place to start, he says. Most preparations, which work by reducing or temporarily plugging pores, contain less than 10 percent of the active ingredient, aluminum chloride. The highest percentage you can get over-the-counter is 12 percent, which can be found in Certain Dri or Xerac antiperspirants.

In Dr. Kelly Hood's Lafayette, Calif., dermatology practice, 80 percent of patients get relief from these or prescription-strength antiperspirants, which contain up to 20 percent aluminum chloride. Yet, doctors agree, proper application is key. And moisture is the enemy.

"If you take your morning shower and towel dry, there's still a significant amount of water on your skin, and it just washes (the product) away," Bank says. "If you apply it at night, when you're calm and dry, there's a better chance of getting it in there and getting effective use."

A dry canvas is so important that your doctor may recommend using a hair dryer before application.

Making subtle lifestyle changes can also tame the schvitz. Avoid outdoor activity from 10 a.m. to 4 p.m., peak sun hours. Drink plenty of water early in the day. It helps sweat do its job, which is to keep the body cool as temperatures elevate. Also, wear loose-fitting, 100 percent cotton clothing, Bank says.

If these modifications don't minimize sweat from the hands, feet, forehead or underarms, you may suffer from hyperhidrosis, or excessive sweating, a condition that poses no health risk but can cause severe distress to sufferers.

Bank estimates that several hundred thousand Americans suffer from it. But because there's no test for the condition, sufferers may be grossly underrepresented.

"Socially it's still not out there," he says. "Hair removal, dermal fillers are totally normal. Sweating unfortunately still remains one of the few subjects people still feel self-conscious bringing up."