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In his latest video, health and fitness YouTuber Will Tennyson takes on the increasingly popular ketogenic diet for 7 days, vastly reducing his carb intake in order to see for himself whether the fat and protein-rich diet is as great for weight loss as so many claim.
For the week-long challenge, Will follows a typical keto macro split: 70 percent fat, 20 percent protein, and a maximum of 10 percent carbs. "Eating all these high-fat foods will be quite the adjustment," he says.
The first meal of the week is avocado, feta cheese and scrambled eggs, which he prepared with a spoonful of butter. "I can't even remember the last time I cooked with butter," he says, before heading out to do his first keto grocery shopping trip, picking up spinach, peppers, avocado, cauliflower, yogurt, eggs, peanut butter, cheese, and the highest-fat meats he could find. "A general rule of thumb is you want to get above-ground vegetables as they're generally a little bit lower in carbs," he explains.
Dinner on D ay 1 is chicken thighs with tahini and feta, and a cauliflower mac and cheese, totaling 81 grams of fat. "Today has been pretty good overall," he says. "I think the only thing that I've noticed immediately is the fact I've been thirsty all day long. I've been needing to drink water the entire day, my entire mouth is like a desert." This is due to "keto dry mouth," a fairly common side effect of starting the keto diet, and increasing the body's fat and decreasing carb intake levels.
By Day 2, Will has already lost 4 pounds overnight. He notes that this is mostly water weight. He continues to enjoy the high-fat food throughout the week, and admits to being "pleasantly surprised" by his performance in the gym.
"Usually when you drop your carbs by quite a bit you will initially notice a decrease in performance, mainly due to the fact that your muscles are so glycogen depleted," he says. "I was very focused, I had tunnel vision the entire time... but it was hard to get a pump and my stamina sucked."
At the start of the week, Will weighs 178.8 pounds, and by the end of the challenge he has dropped 8.2 pounds to 170.6. And while he doesn't necessarily appear leaner, he has definitely found some some benefits to the keto diet. Namely, that the food tastes great, and while the meals aren't necessarily big, they do keep you full and satisfied for longer.
"A lot of people say you can't build muscle on the keto diet, and that's false. All you need is water to stay hydrated, protein to repair and build the muscle, and energy to actually come into the gym and lift the weights. So you don't need carbs, all you need is water, protein, and energy."
