Fad Diet Examples: 15 Popular Diets, Honestly Rated

The most common fad diet examples include the cabbage soup diet, the grapefruit diet, juice cleanses, the lemonade cleanse, the blood type diet, carnivore and one meal a day.

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They look different on the surface, but almost all of them work the same way: they cut calories hard with a strict rule, then the weight comes back when the rule ends.

This list is part of my fad diets guide, where I explain what a fad diet is and how to step off the diet merry-go-round for good. Here, I want to get specific.

I am a NESTA nutrition coach and NASM certified trainer with more than 20 years in this field, and I have watched most of these plans come, go and come back with a new name. Below, each one gets a fair look: what it is, the hook that makes it tempting, and the catch nobody puts on the cover.

Jump to a sectionIn this article7 sections

1. What Turns a Diet into a Fad
2. 15 Fad Diet Examples, Rated Honestly
3. Why Fad Diets Are So Popular
4. What Works Better than Any Fad
5. Your This-Week Plan
6. Quick Questions
7. The Bottom Line

What Turns a Diet into a Fad

Not every diet with a name is a fad. A fad usually has a few things in common.

It promises fast results, it bans a food group or leans on one special food, and it has a short shelf life. It also tends to explain weight loss with a secret mechanism instead of the boring truth about calories, protein and habits.

Keep those markers in mind as you read. You will start to see the same pattern repeat.

15 Fad Diet Examples, Rated Honestly

Here is the quick view first. The details for each plan follow below.

Diet	Promise	Honest Verdict
Cabbage Soup	Fast big drop	Mostly water, very low protein
Grapefruit	Burns fat	No magic enzyme, can clash with meds
Baby Food	Preset portions	Tiny meals, hungry by afternoon
Cookie	Cookies slim you	Very low calorie with extra steps
Five-Bite	Eat anything	Far too little food and protein
Raw Food	Living enzymes	Good produce habit, real food safety risks
Lemonade Cleanse	Flush toxins	Sugar water, muscle loss, rebound
Blood Type	Personal match	No evidence the type matters
Extreme Low Carb	Burn more fat	Works for some, hard to sustain
Carnivore	Meat heals all	No fiber, little long-term research
Juice Cleanse	Full reset	Low protein, lots of sugar
OMAD	Simple fat loss	Hard to meet protein, easy to overeat
Alkaline	Change your pH	Food cannot change blood pH
Celery Juice	Healing tonic	No research behind the claims
Tea Detox	Flat belly fast	Often laxatives, mostly water loss

1. the Cabbage Soup Diet

What it is: Seven days of a homemade cabbage and vegetable soup, plus a rotating list of allowed foods each day, like fruit one day and beef another.

The hook: The scale drops fast, sometimes several pounds in a week, and the soup is cheap.

The catch: Most of that drop is water and stored carbohydrate. Protein is very low, energy crashes, and the weight returns as soon as normal meals do.

2. the Grapefruit Diet

What it is: Half a grapefruit or a glass of its juice with every meal, usually paired with a very low calorie menu.

The hook: The claim that grapefruit contains a special enzyme that burns fat.

The catch: There is no fat-burning enzyme. Any loss comes from the low calorie menu around it. Grapefruit also interacts with several common medications, so check with your pharmacist if you take any.

3. the Baby Food Diet

What it is: Replacing breakfast and lunch with small jars of baby food, then eating a light dinner.

The hook: Portions are already controlled, and there is nothing to cook.

The catch: Baby food is made for babies. The jars are tiny, low in protein and fiber for an adult, and most women are ravenous by evening.

4. the Cookie Diet

What it is: Special diet cookies eaten throughout the day in place of meals, followed by one regular dinner.

The hook: You get to eat cookies and still lose weight.

The catch: It is a very low calorie meal replacement plan wearing a fun costume. It teaches nothing about real meals, and evening overeating is common.

5. the Five-Bite Diet

What it is: Skip breakfast, then eat only five bites of whatever you want at lunch and dinner.

The hook: No banned foods. Burgers and dessert are allowed.

The catch: Five bites is not a meal. It is extremely low in calories and protein, and it leaves you hungry, tired and unable to keep going.

6. the Raw Food Diet

What it is: Eating most or all food uncooked, mainly fruit, vegetables, nuts, seeds and sprouted grains.

The hook: Claims that cooking destroys natural enzymes your body needs.

The catch: Your body makes its own digestive enzymes. Eating lots of produce is a good habit, but strict raw eating makes protein, vitamin B12 and iron harder to get, and raw sprouts, unpasteurized dairy and raw meat carry real food poisoning risk.

7. the Lemonade Cleanse

What it is: Often called the Master Cleanse, it means days of drinking only lemon juice, maple syrup, cayenne and water.

The hook: A dramatic drop on the scale and the promise of flushing out toxins.

The catch: Your liver and kidneys already handle waste, and I break that down in what a detox diet actually does. With zero protein for days, you lose water and muscle, then regain quickly.

8. the Blood Type Diet

What it is: A different food list for type O, A, B and AB blood.

The hook: It feels personal and scientific.

The catch: Reviews of the research have not found that matching food to blood type changes health. People who improve on it usually do so because they cut processed food, which helps everyone regardless of type.

9. Extreme Low Carb

What it is: Atkins-style induction phases and strict plans that cut carbohydrates close to zero.

The hook: Fast early weight loss and fewer cravings for some people.

The catch: That early drop is largely water. Very low carb eating can work for some people, but many find it hard to keep up long term. If you are curious, read my honest look at whether keto is worth it first.

10. Carnivore

What it is: Eating only animal foods: meat, fish, eggs and sometimes dairy.

The hook: Simple rules and big online claims about healing everything.

The catch: Zero fiber, no plants and very little long-term research. Many people see their LDL cholesterol rise, and the diet is very hard to keep socially.

11. Juice Cleanse

What it is: Several days of only fruit and vegetable juices.

The hook: It feels clean, and the bottles look healthy.

The catch: Juice removes most of the fiber, adds a lot of sugar and gives you almost no protein. I cover the research in do juice cleanses work.

12. OMAD (One Meal a Day)

What it is: Fasting about 23 hours and eating one large meal.

The hook: No counting and only one meal to plan.

The catch: Studies have not shown it beats regular calorie reduction. It is hard to eat enough protein in one sitting, and it can feed a binge pattern. Gentler intermittent fasting windows suit more women.

13. the Alkaline Diet

What it is: Favoring fruit and vegetables and avoiding meat, dairy and grains to make your body less acidic.

The hook: The idea that acid causes weight gain and disease.

The catch: Your lungs and kidneys keep blood pH in a tight range no matter what you eat. The vegetables are great. The pH theory is not.

14. Celery Juice

What it is: A big glass of plain celery juice on an empty stomach every morning.

The hook: Social media claims about clearer skin, better digestion and healing.

The catch: There is no research supporting those claims. Celery is fine food, but eating it whole keeps the fiber.

15. Tea Detox

What it is: Teas sold to flatten your belly or detox in a few days.

The hook: A quick flat stomach before an event.

The catch: Many contain herbal laxatives like senna. The flatter belly is lost water and emptier bowels, and regular use can cause cramping, dehydration and electrolyte problems.

Why Fad Diets Are So Popular

A question I hear a lot is why smart people keep falling for these. The answer is not willpower or intelligence.

Fad diets offer certainty and speed. A clear rule feels easier than a hundred small choices, and a fast scale drop feels like proof. When that weight comes back, the diet rarely gets the blame. You do, and that is not fair. My post on why you regain weight explains what is really going on.

What Works Better than Any Fad

The plans that last are less exciting and far more effective.

1. Build meals around protein. Aim for a palm or two at each meal. My list of high-protein foods makes this easy.
2. Fill half your plate with plants. Vegetables and fruit add volume and fiber for few calories.
3. Keep foods you love. Plan for them instead of banning them, so there is nothing to rebel against.
4. Aim for a modest calorie deficit. Slow, steady loss protects muscle and is easier to maintain.
5. Lift something. Two or three strength sessions a week help you keep muscle while you lose fat.
6. Sleep and manage stress. Both shape hunger more than most diet books admit.

Your This-Week Plan

Instead of starting a new diet, try one small shift each day.

1. Day 1: List the diets you have tried and what made each one end.
2. Day 2: Add protein to breakfast.
3. Days 3 to 4: Add one extra serving of vegetables to lunch and dinner.
4. Days 5 to 6: Swap one sugary drink a day for water or unsweetened tea.
5. Day 7: Notice your energy and hunger, not just the scale.

Quick Questions

The Bottom Line

These fad diet examples share one engine: big restriction dressed up with a clever story. The scale moves fast, the plan is impossible to keep, and the weight returns.

You do not need a gimmick. Protein, plants, foods you enjoy, strength work and good sleep will take you further than any cleanse ever could.

This article is for general education and is not medical advice. Talk with your doctor before any very low calorie diet or fast, especially if you are pregnant, take medication, or have diabetes, heart, kidney or gallbladder disease. See a doctor right away if you feel faint, have heart palpitations, or have severe belly pain while dieting.