A 57-year-old man documented eating McDonald's for 100 days on TikTok and says he somehow lost weight

• Kevin Maginnis, 57 from Nashville, said he was going to eat McDonald's every day for 100 days.
• He just hit the milestone, and claims to have dropped from 238 lbs to 179.5 lbs.

A 57-year-old man documented eating McDonald's for 100 days on TikTok, and says he lost 58 1/2 lbs in the process.

Kevin Maginnis, from Nashville, said he was going to eat McDonald's every day for 100 days back in February, and he just hit the milestone

His strategy, he said, was to eat there three times a day, but cut the meals in half. He also vowed to not have any snacks, and only drank water.

"I woke up this morning, and I weighed in at 238 pounds," Maginnis said in his first TikTok of the journey. "And I decided that that is absolutely unacceptable. So I drove down to McDonald's."

Maginnis appeared on NBC's "Today" to explain more. He shared before and after photos, showing a significant change in his body, and said he felt "amazing."

By his reckoning, he ended up at just under 180 lbs.

Per CDC statistics, the change brought him below the average weight for a US male of 199.8 lbs.

He said he allowed himself to order anything on the McDonald's menu and "never counted" the calories.

"So I've eaten Big Macs, quarter pounders, pick a number, with fries," he said. "Don't be bitter while I'm eating my apple fritter and losing weight."

Maginnis also said his health had improved in other ways too. He said his levels of triglyceride — a type of fat that circulates in the blood — was down 205 points, and his cholesterol was down by 65 points.

Maginnis said he was not affiliated with McDonald's and hadn't been sponsored by them to do the challenge, but they did send him a "gift box."

He said he chose McDonald's in the first place because his nickname was "Big Mac" and he thought it would be a good fit.

Tara Schmidt, the lead registered dietitian for the New Mayo Clinic Diet, told Fortune that Maginnis' method worked because it was calorie-based weight-loss — he was simply burning more calories than he was consuming.

However, weight is not the only measure of health, she pointed out.

"In the realm of food choices, it's also notable to consider the quality of food being consumed and its impact on the body," she said.

Highly processed and fried foods, for instance, can increase our risk of developing heart disease, type 2 diabetes, and cancer, due to the inflammation they can cause. One study from 2021 found that one small portion of fried food per week was associated with a 3% increased risk of heart attack and stroke, a 2% increased risk of heart disease, and a 12% increased risk of heart failure.

Maginnis said health was his priority for his next 100 days, telling the Today Show he was going to attempt a 100-foot rope climb. But not before his last McDonald's meal — six chicken nuggets.