Tomorrow, a Pittsburgh adventurer with type 1 diabetes will embark on his next challenge: scaling Lhotse, the world's fourth-highest mountain.

Will Cross, 40, already has trekked to the North and South poles and climbed the highest peaks on the seven continents, including Mount Everest. He's the first person with type 1 diabetes to accomplish such feats.

A professional adventurer, he receives financial sponsorships from companies involved with diabetes care, including insulin producer Novo Nordisk Inc., and Animas Corp., which produces insulin pumps, along with Kobold Watches of Pittsburgh.

The University of Pittsburgh Medical Center and Diabetes Institute also have studied Mr. Cross, who has shown no adverse health reactions to his expeditions. He's proven that being fit and prepared, along with maintaining good blood sugar levels, eating the right diet, and protecting his medications and diabetes gear, are necessary in high-risk adventures.

He also does motivational speeches on living with diabetes and refusing to let the disease undermine one's goals. His Web site is www.willcrossmotivates.com.

Once he arrives in Katmandu, Nepal, he'll spend weeks preparing for the trek, hiking and acclimating his body at high altitudes, before he attempts the weeklong Lhotse climb in May, when weather and wind conditions provide a brief window of opportunity for climbing.

An unexpected challenge may arise from climbing restrictions enacted through May 10 as part of China's effort to avoid "Free Tibet" protests when it sends climbers bearing the Olympic torch to the summit of Everest from the Tibetan side as a prelude to hosting the 2008 Summer Olympics in Beijing. Because Lhotse, which is on the border of Nepal and Tibet, shares some climbing camps with Mount Everest, its climbers could be affected.

If that happens, Mr. Cross said he'll turn his attention to climbing another Himalayan peak.

It took him three attempts to reach the summit of Mount Everest, finally accomplishing that feat on May 23, 2006.

His current goal is the Giant Mountain Challenge, which involves scaling six Himalayan peaks higher than 26,000 feet, the first of which is Lhotse.

His first attempt at Lhotse last year ended about 1,000 feet short of the 27,940-foot summit -- or 5.4 miles high. He turned back because of unfavorable weather and snow conditions.

"My job is to manage risk and assess it accurately," Mr. Cross said. "Last year, I assessed the snow, and it was not the right consistency. It didn't feel right.

"It's tempting, when you put two months and the money into a climb, to go for it, but then you're not managing the risk but ignoring it," he said. "That's when you get into trouble. It's like a drunk driver getting into a car and turning on the ignition."

Although 1,095 feet shorter than Everest, Lhotse is steeper and requires more technical climbing ability.

"As with Everest, you don't get to make mistakes," Mr. Cross said. "You have to know when to go home."

That's particularly important for Mr. Cross, who has a wife, Amy, and six children ranging in age from 3 to 17 -- or as he puts it, "from Huggies to hormones."

Once in Katmandu, he'll trek for 10 days, going from elevations of 9,000 to 17,000 feet. He'll make partial climbs to acclimate his body to thin air and the weaker gravity, then return to base camp.

Once he's acclimated and conditions are right, he'll begin the main climb. His diabetes adds to the considerable challenges.

Type 1 occurs when an autoimmune response damages or destroys insulin-producing beta cells in the pancreas. Without enough insulin, which allows blood glucose to enter cells, blood sugar levels rise to dangerous and eventually deadly levels.

Controlling one's blood sugar is a daily challenge for anyone with type 1, let alone one who climbs mountains. A too-high insulin dose causes blood sugar levels to dip to dangerous levels, causing one to lose coordination and ability to think coherently. Known as hypoglycemia, low blood sugar can lead to unconsciousness and death.

Mr. Cross also must wrap insulin supplies in aluminum foil and athletic tape for storage in a thermos to prevent freezing. With temperatures dipping as low as minus 30 degrees Fahrenheit, he must sleep with his insulin to keep it warm.

While climbing, he's unable to test his sugar, so he takes glucose gel throughout the day to maintain a healthy level and generally "grazes" all day long on cheeses, dry meats, chocolates and high-calorie fatty foods to maximize calories and counter the cold weather.

The diet goes counter to general recommendations for people with diabetes who typically are advised to eat foods low in sugar, carbohydrates and fats.

Even though he eats fewer calories during a climb, he still takes extra insulin because stress and environmental conditions cause blood sugar levels to rise. He said his appetite drops during a climb, adding another uncertainty.

"I always have to have food on my person," he said, noting the importance of drinking lots of water. "The big thing is anticipating my [blood sugar] lows. I cannot afford not to be functional."

Mr. Cross said the Lhotse climb is important to his continuing effort to demonstrate that diabetes, when properly managed, doesn't have to block one's goals.