Dieters are clinically proven to lose up to 7 lbs. in a week, so we had to try it for ourselves.
What is it: The Sirtfood Diet, created by nutritionists Aidan Goggins and Glen Matten, and a favorite of trainer Pete Geracimo, who has all of his clients — Adele and Pippa Middleton included — follow the plan.
Who tried it: Julie Mazziotta, PEOPLE Writer/Reporter
Difficulty: 9/10 — So. Hungry. (At least for the first three days!)
In between racking up Grammy Awards, recording three hit albums and becoming a mom, Adele has quietly slimmed down with the help of trainer Pete Geracimo. Under his instruction, the singer hits the gym (whether she wants to or not), and follows the Sirtfood Diet, which focuses on about 20 “wonderfoods” like arugula, celery, cocoa, coffee, red onion and more.
I have no kids and a terrible singing voice, so testing out the diet for myself seemed like my only option to become more like Adele. Plus, dieters are clinically proven to lose 7 lbs. in the first seven days on the program, and I’d be A-Okay with that. So I gladly volunteered to try out week one.
Step one, before the diet actually started, was to read through The Sirtfood Diet and make a grocery list. On the first three days of the program I would be slurping down three green juices — made up of kale, arugula, ginger, green apple, parsley, lemon and macha powder — and just one meal per day. This should have triggered a giant red flag for me, but the meals I did get sounded great — miso and sesame-glazed tofu with ginger and chili stir-fried greens, shrimp stir-fry with buckwheat noodles — plus after three days you go up to two meals a day, and two green juices. So I happily went off to Whole Foods.
The recipes thankfully are filled with ingredients you can find at any grocery store, anywhere in the country — except for one thing: buckwheat. I couldn’t find it on my first shopping trip (the only reason why I went to Whole Foods for my groceries in the first place), and it took me another two tries to finally locate the grain (thanks, Chelsea Whole Foods!).
Buckwheat and the other sirtfoods are the focal points of the diet because they’re high in polyphenols — a plant-based nutrient that Goggins and Matten say are great for the digestive system.
Polyphenols “activate a powerful recycling process in the body which clears out cellular waste and burns fat,” the duo write in the book. “They do this by activating our sirtuin genes — also known as our ‘skinny’ genes. Indeed, these are the very same genes that are activated by fasting and exercise.”
That morning, perfectly content after enjoying my usual three (healthy-ish!) meals the day before, I cracked open my first green juice to start the diet (I will admit here that I cheated a bit from the start — I don’t have a juicer, nor the space in my apartment to store one, so I bought juices that matched the ingredients in Sirtfood‘s recipe from Juice Press and Pressed Juicery in New York City). Pretty good! I’ve never been a regular green juice-drinker, but this was enjoyable enough.
I kept sipping throughout the day, and started getting my usual hunger calls around 11 a.m. I have a pretty severe snack addiction, but I at least go for the healthy stuff, like pistachios and granola bars, and this was normally when I get my fix. But I pushed through. Goggins and Matten say that you can eat your one meal at any time of the day, so I decided to go for 4 p.m.
By 1 p.m., I was miserable and starving. The green juice did absolutely nothing to curb my hunger, which makes sense — nothing in it has real staying power. I regularly write the What I Eat columns, and I kept thinking about the nutritionists who talk about the need for meals with protein to keep you satisfied, something I was severely lacking. My day piled up, so I somehow didn’t actually eat until 5 p.m. Luckily, the meal was DELICIOUS. I went for the aforementioned miso-glazed tofu, and I would make this any day of the week. I even managed to save part of it to eat when I got home from work as a “dinner” (is it against the rules to split up the one meal? I was too hungry to care).
More green juice. More hunger.
Today’s meal was harissa-baked tofu with cauliflower “couscous.” I’m not vegetarian, but I’m not a big fan of shrimp, the other option that day. I probably should have gone with it anyway though — this meal was a big miss for me. It again lacked anything satisfying, so I was miserable the entire day, particularly when I somberly followed my friends to dinner at Sweetgreen (probably my all-time favorite fast-casual restaurant) that night and sipped the ubiquitous green juice as they munched on salads. Yes, I was jealous of salads.
You guessed it! I had green juice for breakfast.
My meal today was a kale and red onion dal with buckwheat, and WOW. I loved it. I wanted piles of it. But my one portion was surprisingly satisfying — I think at this point my appetite had gone down from eating under 1,000 calories a day, plus the dal included plenty of satiating ingredients, like lentils, buckwheat (I found it!) and healthy fat-filled coconut milk. I don’t weigh myself, but by day three I was comfortably wearing my tightest pair of skinny jeans, and my normally rounded stomach was much flatter.
The only remaining problem? I’m someone who exercises regularly, and hard. I go to CrossFit three times a week, sometimes more, and I run or swim on the other days. With such a low calorie count that wasn’t recommended (I emailed Goggins, who said, “The mild calorie restriction plus the high intake of sirtuin-activating nutrients is creating a mild stress on our cells which causes sirtuin activity to strongly kick in. Too much exercise just causes too much stress, which could then be detrimental”), but I love the head-clearing benefits of exercise. I went to CrossFit that night, and knowing I wanted to go again in the morning for the usual Saturday workout, I hard-boiled two eggs and ate them with Old Bay and drizzled extra-virgin olive oil, my favorite. It was beyond necessary.
I could finally eat two meals a day — hooray! But my tough workout unsurprisingly didn’t go well on such little food over the last three days. So with the increase in food on the plan, I decided to switch things up — I would go back to eating normally, and just try out the other recipes for the rest of the week. I’m stubborn and highly competitive, so it was frustrating to “fail” at the diet, but I also really, really love food, and skipping one to two meals a day was not worth it to me.
The rest of the week:
The other meals I tried — pan-fried salmon with caramelized endive, arugula and celery leaf salad (it also has avocado!); Tuscan bean stew; the sirt super salad; the sirtfood omelet — were all similarly fantastic. I want to give a hearty props to Goggins and Matten for crafting recipes that are delicious and filled with normal ingredients — plus they were often one-pan meals, which is key for someone without a dishwasher nor a person to do the dishes for you (which I’m of course assuming Adele has — livin’ the dream).
If you are immune to hunger and really enjoy green juices, go for it (and check with your doctor beforehand)! If you’re more like me, skip week one, and go straight to week two, when you get to enjoy three full and truly excellent meals a day. And you can still pretend to be Adele.
NOTE: It is recommended that women eat at least 1,200 calories per day, and men eat at least 1,800 calories per day.
This article originally appeared in People