The Truth Behind America's 8 Biggest Diet Fads

ELLE editors tested out the most extreme diet plans. Find out who will lose the most (without losing her mind).

1. The Alkaline Diet
The plan: According to Honestly Healthy, a book by British nutritionist Vicki Edgson and vegetarian chef Natasha Corrett-about which Victoria Beckham enthusiastically tweeted in January-eating a diet of predominantly alkaline foods (veggies, mostly) and avoiding those that create acidity in the cells (carbonated drinks, red meat, dairy, bread) will balance the body's pH, for better skin, digestion, and immunity.
Editor's take: Eating the recommended 80:20 alkaline-acid ratio was easy (typically, salad with a side of fish), and I never craved sugar, a high scorer on the evil-acid index. However, I failed to give up coffee and wine, so I drank lots of superalkalinizing fresh-squeezed lemon for balance. To check that my pH never dipped below the optimum 7.35, I tested it daily with a saliva-activated strip. Like science class!
The payoff: Turns out dropping acid is as much a stop-feeling-like-crap life change as it is a weight-loss strategy. Three weeks in, I feel peppy and look debloated. A weekend spent mainlining meat, bread, and booze (I was in France!) was a lesson learned: My pH dropped to 6.5, my complexion dulled, and I felt oafish.

2. The Baby Food Diet
The plan: Celebrity trainer Tracy Anderson kicked off a pureed-food craze a couple years ago when she reportedly advised clients to replace two meals a day with jars of Gerber (seriously), plus a healthy dinner. Anderson has since denied endorsing the diet, but Hedi Slimane and Lady (goo-goo?) Gaga are rumored to be devotees.
Editor's take: Shamed by the prospect of loading a grocery cart with infant food, I order 100 jars from Fresh Direct (the delivery guy still gave me a strange look). I tried mixing vegetables with fruit and protein, but after gagging on the beef pilaf, I stuck with the sweet fruit varieties. In fact, I became a pureed banana and apple addict, which flooded my system with so much sugar that I felt high. And moody. In other words, a total wreck.
The payoff: I have never wanted bread more in my life (maybe because I craved texture?) and would actually go home and cram four slices in my mouth at the end of each day. So much for a healthy dinner. I did lose four pounds by day five, but I was also miserable and hallucinating. Not worth it.

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3. The Blood-Type Diet

The plan: Developed by Peter J. D'Adamo, ND, Eat Right 4 Your Type (a classic, first published in 1997) is based on the premise that each blood type requires a specialized diet to aid weight loss and improve conditions such as asthma, heartburn, and headaches.
Editor's take: In the past, I've tried veganism and other elimination diets, which left me mostly hungry and unsatisfied-maybe because Type A's, according to D'Adamo, are more suited for vegetarianism. For my O type, meat is actually recommended, which is great because I'm very active. It was easy to check which foods got the green light using the Blood Type Diet app-though it turns out a few of my diet staples (coconut, corn, avocado) are no-no's.
The payoff: After a month on the plan, I'm a believer. Although I miss some of my favorite foods (dairy is redlined for O), the plan has actually expanded my diet. I used to avoid fruits, but cherries, pineapple, and figs are okay. Now I eat meat without guilt, I stay fuller longer, and the weight is slowly coming off.

4. The Clean Program
The plan: Introduced in 2009 by cardiologist Alejandro Junger, MD, the Clean Program's 21-day detox excludes common allergens and inflammatory foods. Its dining plan of two liquid meals a day (DIY fruit-and-almond-milk smoothies are fine, though Junger sells a $425 bundle of vitamin supplements and protein powders on his site) and one solid lunch has found favor with svelte foodies such as Gwyneth Paltrow.
Editor's take: Nixing booze, coffee, cheese, gluten, and sugar for three weeks sounded like a rejection of life, but Clean's expansive list of approved foods introduced me to new staples like quinoa and kale. Other than a brief breakdown at the end of week one that involved salaciously pinning dozens of salted caramels to an ad hoc Pinterest board, for the most part I didn't miss my old diet. In fact, when my 21 days were up, I extended the plan for 14 more.
The payoff: In the mornings I felt awake without a shot of espresso. At night I fell asleep without a glass (or three) of red. I shed eight pounds in the first three weeks and an additional four by week five-along with my double chin and puffy eyes-without ever feeling hungry. And, best of all, so far the weight has stayed away.

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5. The French Woman Diet
The plan: Pin-thin fashion maven Carine Roitfeld has declared she follows the "French woman diet," which consists of small portions of rich foods (think steak, cheese, and tuna tartare). This requires sit-down meals-no mindless chowing while House of Cards unspools in the background-and prohibits packaged food and (I'm grateful to say) exercise.
Editor's take: I signed on to essay Roitfeld's eating plan because it was the only one of the bunch that allows for alcohol and dessert, but it turns out our tastes are remarkably in sync: Mini delicacies such as sashimi are cornerstones of my diet, so it was easy enough to adapt. And surprisingly, as unscientific as Roitfeld's "diet" may be, it actually has some compelling support: Studies have shown that the calcium found in dairy (including my fromage) can speed weight loss, and research published in 2012 revealed that a compound in red wine can block the development of fat cells.
The payoff: Because this method encourages you to savor each meal (and drink-santé!), I have yet to feel deprived. All in all, it was a fairly painless, at times even delicious, way to spend a week. However, it may not be radical enough, since, between the lack of exercise and the permissive menu, it hasn't yet resulted in any weight loss, either.

6. The Paleo Diet
The plan: Paleo Diet devotees follow a Stone Age-inspired regimen featuring hunter-gatherer staples such as lamb, poultry, bison, and other lean game. Modern favorites wheat, dairy, and legumes are out, and you can forget juices-Vitamixing wasn't an option 10,000 years ago. There are scant studies to prove the diet's efficacy, but at the very least, I figure ditching junk food can't be bad.
Editor's take: Swapping Seamless deliveries for home-cooked meals meant more hours in the kitchen cranking out dishes I adapted from Loren Cordain's 2010 best-seller The Paleo Diet Cookbook-grass-fed meatloaf with almond meal, vegetables sautéed in coconut oil, and cocoa-covered nut balls with coconut shreds-and less time in the gym. I loved having an excuse to eat heartier foods, but most sent me into a sluggish food coma. Not to mention skipping happy hour gave me major FOMO.
The payoff: After two weeks, I'm up a couple pounds, but I swear my nonexistent biceps have gotten more pronounced and my stomach has flattened-success! Life without packaged food actually feels chic. When my annual physical reveals a major spike in cholesterol, though, I decide to return to my mostly meatless previous diet, sans wheat and dairy.

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7. The Karl Lagerfeld Diet
The plan: The Karl Lagerfeld Diet (published in a 2004 book) was devised for the Kaiser by nutrition specialist Jean-Claude Houdret, who helped the designer drop 90 pounds in the early aughts. It consists of three phases: a 900 calorie-a-day limit for two weeks; 1,200 a day for one week; and then maintenance at 1,600.
Editor's take: As a dieting neophyte, the petite portions of vegetables (sautéed or raw) and bland shakes (using Lagerfeld's favorite: chocolate flavored, sugar-free powdered protein sachets) in the first phase left my palate and stomach longing for more. The subsequent stages allowed more substantial options, including grilled chicken, avocado on toast, and Greek yogurt, but portions were still brutally small. I tried to curb my appetite with Diet Coke (Lagerfeld says he drinks 10 cans a day), but in the end, my saving grace was an occasional cheat.
The payoff: Despite the gnawing hunger, I have no regrets about eating à la Lagerfeld for a week. I lost four pounds and my skin was clearer than it had been in months. Surprisingly, my day-to-day diet has since become slightly more portion conscious-something I've attributed to the German's voice of God commanding me to take a pass on the bread basket.

8. The Pil-Sook Diet
The plan: A fad in South Korea, the Pil-sook Plan comes from hit K-drama Dream High. When pop-star wannabe Pil-sook wants to drop 65 pounds in 200 days, her teacher paraphrases twentieth-century nutritionist Adelle Davis' famous rule: "Eat breakfast like a queen, lunch like a commoner, dinner like a pauper." The catch: No liquids after 7 p.m. and mandatory daily 30-minute jump-roping sessions.
Editor's take: Pil-sook's teacher has science on her side: A study in the American Journal of Clinical Nutrition found that eating a high-protein breakfast reduces the release of ghrelin, a hormone that stimulates hunger. Initially I had zero appetite in the mornings, so my first few Queen-size breakfasts (a veggie omelet, yogurt, and fruit) felt like a waste. But by day three, after two nights of starving on my Pauper meal-plan, I woke up ravenous.
The payoff: Anything I crave, I'd sneak into my Queen breakfasts, so it was easy to do the Pauper dinner knowing I would wake up to a big meal. During my second jump-rope session, my neighbor knocked on my door to ask what was causing the noise. I switched to speed walking (on a treadmill, so I can stream Dream High 2 on DramaFever)-and still lost weight.

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