A man who lost 40 pounds — and cut 10 inches from his waistline — recommends walking, protein swaps, and drinking vinegar water

• A CEO lost 40 pounds with recommendations from a "digital twin" on his phone.
• The Twin encourages him to walk, showing him the impact movement has on his blood sugar. 
• He's also been surprised to learn more about the benefits of starting his meals with some veggies. 

Devlin Donaldson didn't think he could take another step.

"I got to go home," he remembers telling his wife, as they strolled around the neighborhood. "I'm exhausted."

He'd just signed up for a health program designed to get him off his medications and put his type 2 diabetes into remission. It's called Twin Health, and in addition to making personalized recommendations for him on his phone about what to eat and how much to sleep, it also counseled him to sneak more movement into his days, by aiming to log about 10,000 steps in his smartwatch.

"Like any workout thing, it's always the most painful in the first few days," he told Business Insider. "When they said, 'you've got to walk 10,000 steps,' I went, 'you're crazy. That is not going to happen.'"

But it did.

Now, Donaldson says those extra steps have played a surprisingly crucial role in not only managing his weight, but also regulating his blood sugar, improving his cholesterol, and lowering his blood pressure.

Here are three of the biggest ways he lowered his risk of early death, while also putting his diabetes in remission, losing around 40 pounds, and eliminating 10 inches from his waistline.

Tip 1: Get up for a walk

These days, if Donaldson notices his blood sugar going up on his continuous glucose monitor, he feels empowered to take action.

"There's all kinds of things I know now I can do to stop that rise in glucose," he said. "I know what to do to counteract that."

One of the most straightforward is just getting up for a walk. It wasn't easy at first.

"The first time I went out to walk, my wife was walking with me. I'm like, "'How far have we gone?' She's like '2,500 steps.'" He was spent.

Now, he enjoys going on walks that are up to four times as long as that initial hike.

"As long as I keep it consistent, I actually feel better at the end of five miles than I do when I start," he said.

Experts say you don't have to go all in on the 10,000 step marketing myth to derive serious benefits from more daily movement, though, and Donaldson agrees.

"If anybody can commit and say, 'I'm going to do this for a month, or for two months,' and just do it for that long, and you don't even have to get to the 10,000," he said. "Get to 6,000, get to 8,000."

Recent studies have suggested exactly what Donaldson grasps intuitively from his experience.

While 8,000 steps does seem to be a kind of sweet spot where a bunch of longevity benefits kick in, researchers are starting to collect data showing that even walking 2,000 to 4,000 steps a day still dramatically cuts a person's risk of death, especially from heart issues. If you're pressed for time or energy, even bounding out the door for a brisk additional 500 steps would make a cardiologist's heart sing.

At the end of the day, what's more important than the number of times your feet hit the ground is really what all these step counters are indirectly measuring — enough regular movement to keep your heart pumping, blood flowing, and oxygen moving through the body.

After about three or four months of still feeling lethargic and depressed, Donaldson said his "energy flipped."

"I just reached this point, like an inflection point," he said.

Suddenly, he was running around the house, taking out the trash and doing the dishes. "I got all this energy, and that has continued. From that point, my energy went off the chart, and that's an unbelievable gift to have energy to live life, enjoy it, and engage in it again instead of feeling heavy and sedentary and tired all the time."

Tip 2: Eat non-starchy veggies first, then protein, then carbs

Another piece of advice Donaldson's twin suggested to him was that he enjoy some non-starchy veggies ahead of the rest of his meal. Sometimes he'll have some asparagus, other meals it might be celery or cauliflower. He also likes to snack on a little bit of broccoli and cheese, or have a salad before the rest of his dinner.

Nutrition experts suspect that, for people with type 2 diabetes, front-loading vegetables in this way can help control blood sugar and slow down digestion.

"That's really good advice actually, in type 2 diabetes, to have either the veggies first and/or the protein, and the carbohydrates last," registered dietician Nicola Guess, who studies prevention and management of type 2 diabetes at Oxford University, told Business Insider. "There's good evidence that's a good strategy."

For people who do not have diabetes, it's not clear there's necessarily much benefit to eating like this.

Tip 3: ACV is slightly more controversial, but can also help control blood sugar

On the advice of his digital twin, Donaldson has also started diluting a bit of apple cider vinegar into his water glass throughout the day. He usually does one teaspoon of ACV into an 8-ounce glass.

He remembers his grandmother talking about the health benefits of this type of vinegar when he was a child, but he just assumed it was an old wives' tale. Now, with his continuous glucose monitor on, he has noticed that drinking ACV does indeed help lower his blood sugar. It's a popular internet strategy, propelled by influencers like the "Glucose Goddess" and others, but independent nutrition experts aren't totally sold on it as a go-to hack.

"There are healthier ways to get your glucose down," Guess said.

Though a couple of tablespoons of ACV a day diluted in water or salad dressing is probably pretty safe, Guess worries about the potential for long-term negative effects with larger doses, since ACV is so acidic. Twin Health says it doesn't recommend the strategy to everyone, this is just one technique that has worked well for Donaldson. ("We don't recommend ACV to people with acid reflux, dental problems, or other medical conditions impacted by high acidity foods," the company said in a statement to BI.)

Donaldson, though he doesn't love the taste of the vinegar, and doesn't feel any different after taking it, does enjoy watching how blood sugar spikes in his CGM are blunted by his new, slightly sour potion. He appreciates how the app has taught him smarter ways to eat and move, but he also knows all of these tips and tricks are nothing without his own effort.

"At the end of the day, you're the one going for the walk and deciding what to eat," Donaldson said. "My twin is along for the journey with me, but it is my journey and I've got to invest."