(CNN) -- Brian McLaughlin used to arrive 20 minutes early to on-site client meetings. He would drive around the parking lot to find a space close to the building, and then go inside to cool off from the short walk. The extra weight he was carrying made him sweat constantly inside his suit.
McLaughlin had struggled with weight his entire life. At age 10 he weighed 140 pounds; at age 20 he was 280 pounds. By 30, he had reached his heaviest weight of 330 pounds.
In 2010, McLaughlin moved from Ireland to New York, after landing a job as software architect for the New York Stock Exchange. He went out for lunch and dinner with his new American co-workers in an attempt to socialize and make friends -- sacrificing all hopes of eating healthy.
"I was living a bachelor lifestyle," says McLaughlin. "I would eat and drink a lot, which played havoc with the weight."
He tried The Atkins Diet and Weight Watchers but nothing seemed to click.
He watched as his mother lost 50 pounds on a diet program called Slimming World, which advocates dieting without deprivation of the foods you like. And he saw his girlfriend shed 100 pounds on Weight Watchers.
Seeing living proof that people can lose weight inspired him to make some changes of his own.
A social sacrifice
It was tough to stop going out to eat for lunch and dinner, McLaughlin says. He used to go out with his co-worker a couple of times a week and indulge in a half-dozen strong cocktails before (and after) lavish three-course meals.
"I'd usually have an appetizer of cured meats, the largest available steak, or a rack of lamb for mains, a side of vegetables sautéed in butter or oil, rich desserts like molten chocolate lava cake or chocolate ganache and a cheese board with dessert wine to finish," says McLaughlin.
Between the two of them, McLaughlin says they would split three bottles of wine with dinner.
"I can't remember a meal where I walked away not feeling completely stuffed to the point of almost being sick," he says. "Dinner and drinks used to add up to 5,000 calories alone."
Now he follows the Slimming World plan and prepares his meals at home. They usually consist of fruit and either chicken rubbed with dry spices, or fillet and broccoli or cauliflower. When he does eat out, he chooses carefully.
"I love the dining experience and social aspect," says McLaughlin. "But I realize a 6- or 8-ounce filet is more than enough now."
He also tries to skip cocktail hour.
"Now I tend to drink wine only, and I enjoy and savor the taste instead of just drinking for the sake and experience," McLaughlin says.
Different diet, same result
McLaughlin's girlfriend, Allison Dressler, says she found it hard to cook in the beginning of their relationship due to their different diet meal plans.
She followed Weight Watchers, which focuses on a point system to limit calories. For Slimming World, McLaughlin would worry about every drop of oil, butter or cooking spray because those were restricted under the diet plan.
"As we cooked more and more we realized a lot of the things he eats are actually good for me," says Dressler. "And a lot of things I eat aren't that bad for him, either."
Neither Dressler nor McLaughlin have gym memberships; they simply walk a few miles a couple of days of the week. McLaughlin didn't want to drastically change his workout plan because he feared he wouldn't be able to stay motivated.
"It's hard to go to the gym after work," he says. "I really wanted to focus on controlling my eating habits more than anything."
That strategy worked. In the last three years, McLaughlin has lost 140 pounds.
McLaughlin now goes to work more than two hours earlier than he used to and finishes earlier, which has increased his productivity.
"I don't feel that constant sluggish feeling anymore," he says.
His energy has also increased dramatically; he no longer lies in bed watching The Food Network until the afternoon.
When he first moved to New York, his only hobby was eating and drinking -- now he spends his weekends researching farmers markets to visit, chili festivals, wine stores and fruit-picking spots.
The couple recently went on vacation and chose to walk to their terminal rather than take the moving pavements like they use to.
Dressler says its these small changes that make the biggest differences.
"A lot of my life still revolves around food and drink, but it's no longer destructive," says McLaughlin.