The cereal diet and other eating fads we wish we could forget

Diets to avoid at all costs

Throughout the centuries, people have tried just about every diet going in the quest for a slimmer waistline and better health. However, fad diets are notoriously difficult to sustain – and in some cases, they can be dangerous (and even deadly). Here, nutritionist Angela Dowden rounds up some of the most eccentric, weird and risky diets from the 1500s to the present day, counting down to the most bizarre.

Read on to learn about some of the strangest and most gruesome diets from history, including some people still follow today.

We've based our ranking on the strangeness, danger and ineffectiveness of each diet, and on the opinions of our well-travelled (and well-fed) team. The list is unavoidably subjective.

34. The Banting diet

The idea of a low-carbohydrate diet may seem old fashioned to us now, but it was a novel thing for English undertaker William Banting to promote in the 19th century. His 1863 pamphlet, Letter on Corpulence, addressed the public and discussed his experience with the diet. It was so popular that his name became shorthand for dieting – people would say that they were ‘Banting’ as a reason for their abstinence from foods high in carbs. However, like any restrictive diet, it posed a real risk of nutrient deficiencies.

33. The macrobiotic diet

Proponents of some diets claim they have a variety of health benefits, despite little or no evidence to back them up. This is the case with the macrobiotic diet popularised in the 1930s, which is based on a Japanese diet – and which some say is helpful for people with cancer. However, while eating a balanced diet with whole grains, vegetables and legumes is always a good idea, cancer experts caution against relying on diet alone as a treatment. Plus, because the diet contains no dairy, it can add up to a lack of essential nutrients.

32. The sirtfood diet

The sirtfood diet advocates eating a selection of foods – including kale, walnuts, strawberries, onions, chilli, chocolate and red wine – which are meant to boost the 'SIRT' proteins in the body that raise metabolism levels and reduce inflammation. The plan, which was created in 2016 by two UK-based nutritionists, Aidan Goggins and Glen Matten, involves drinking a green juice every day and following a calorie-restricted diet. The diet gained popularity when it was linked to famous singer Adele, who has since said she has never followed the plan. Meanwhile, experts say there's no specific research that proves sirtfoods to be beneficial.

31. Celery juice

The diet fad of fresh celery juice was kicked off in 2018 by Anthony William, an LA-based wellness influencer who calls himself the 'Medical Medium' and the 'originator of a global celery juice movement'. It's claimed that drinking a pint or more of celery juice a day helps to boost weight loss, tackle skin problems and raise energy levels, among other supposed health benefits. Really, though, there’s absolutely no evidence that it's more or less healthy than any other vegetable juice.

30. The Hallelujah diet

In the early 1990s, US Reverend George Malkmus created this biblical diet – based on only consuming things that Adam and Eve might have eaten in the Garden of Eden. The diet, which recommends eating plenty of fruit and vegetables, also advocates using supplements from the Reverend's company (a sure sign of a fad diet). Apart from anything else, we're pretty sure that Adam and Eve wouldn't have had access to any local health food stores to get their hands on nutrient-boosting tablets.

29. The 'move away from the swamp' diet

In 1727, writer Thomas Short observed that overweight people often lived near swamps. He published a treatise entitled The Causes and Effects of Corpulence, outlining that the only logical way to lose weight was to move further away from any swamps. Obviously, no connection between swamps and weight actually exists, but there is some evidence that people living in rural areas face a higher risk of obesity.

28. The Lord Byron vinegar diet

British poet and politician Lord Byron apparently lost a significant amount of weight between 1806-11, surviving on a diet of biscuits, soda water and large quantities of vinegar. Apple cider vinegar is still held up as a weight loss aid, but there's no evidence it works. In fact, drinking large doses of vinegar can be dangerous; Byron swigged so much that he had stomach problems.

27. Rubber underwear

Rubber underwear was the Spanx of the 19th century, with people hoping to hold in their wobbly bits and lose weight – all thanks to the sweating caused by wearing such garments. Unfortunately, the fluid loss only caused a temporary reduction in weight, and the sweaty rubber undies made skin more vulnerable to infection.

26. The 'chastity' diet

Whole wheat Graham flour is named after Reverend Sylvester Graham, who was an advocate of temperance and vegetarianism in the 19th century. He also believed that white sugar, refined flour and spices promoted sinful passionate urges and were best avoided. It's likely, then, he would be a bit upset that his legacy lives on in the s’more – a traditional US campfire favourite in which two Graham crackers are sandwiched together with a layer of melted marshmallow and chocolate.

25. The corn flakes diet

Replacing two meals a day with a bowl of Special K cereal was a diet phenomenon in the early 2000s, but the cereal diet dates back much further. Dr John Harvey Kellogg created corn flakes in 1894 as a food for the patients of the Battle Creek Sanitarium in Michigan, USA, where he was superintendent. Like Sylvester Graham before him, Kellogg believed in making foods as bland as possible to curb romantic urges.

24. Hot sand to 'sweat out fat'

In the 18th century, it was believed that covering your body in hot sand would make you sweat more, and therefore lose fat. As we now know, it’s actually only water and salts that are lost through sweat. Plus, any water weight lost is only temporary – you put it straight back on when you rehydrate. So, unfortunately, this fad just left people hot and bothered, with sand in hard-to-reach places.

23. The milk diet

Bernarr Macfadden was an American bodybuilder who, in 1923, advocated consuming nothing but eight to 12 pints of milk per day for peak fitness. He went on to say that, while he realised sticking to such a stringent diet based on milk would hinder people taking part in many activities, it was essential to stick to the regime if you wanted to see results. While milk is of course nutritious, it lacks vitamin C and fibre, and it can cause digestive problems in people with lactose intolerance.

22. The Inuit diet

1930s Arctic explorer Vilhjalmur Stefansson of Sweden believed that a high calorie diet of whale blubber, caribou and raw fish was a great idea, because the Inuits who lived on this diet were slim and healthy. While this diet is high in heart-healthy omega-3 fats, it lacks fruit and vegetables – and it ignores the fact that the Inuit people are genetically adapted to their diet and burn a lot of calories due to their active lifestyles.

21. Master Cleanse diet

The Master Cleanse diet – a liquid-only 10-day diet where you drink a lemonade-like beverage, a salt-water drink and a herbal laxative tea – started in the 1940s. However, incredibly, it's still used by people who want to lose weight fast. In an interview with Oprah, Beyoncé revealed that she did the cleanse to lose weight for her role in 2006 movie Dreamgirls. It'll likely lead to weight loss because it's so low in calories, but it’s short on nutrients and impossible to sustain in the long term.

20. The cabbage soup diet

The cabbage soup diet became popular among 1950s housewives who wanted to lose weight quickly, and it's been in and out of fashion ever since. Dieters eat three to four servings of cabbage soup a day, which fills your stomach, but side effects like fatigue, light-headedness and flatulence are common. The diet is very low in calories, so you'll lose weight, but eating cabbage soup alone won't provide enough protein or energy to maintain good health.

19. Chewing and spitting

In 1903, American dietician Horace Fletcher became known as the 'Great Masticator' thanks to his belief that chewing food for 100 bites per minute would result in weight loss – making a person stronger, as well as limiting the amount of food consumed. Followers were also encouraged to spit out whatever was left in their mouths that hadn’t turned to liquid when the chewing was done. Gross!

18. The grapefruit diet

Obviously, replacing a meal with a piece of fruit is going to reduce your calorie intake and help you lose weight – but surviving on so little isn't the healthiest of solutions. Popular in the 1970s, the grapefruit diet involves eating a grapefruit at every meal, sometimes with nothing else. Interestingly, research has since found that certain components in grapefruit may have a beneficial effect on blood glucose and insulin levels, at least in mice, and that could help prevent obesity.

17. The Hollywood cookie diet

The Hollywood cookie diet launched in 1974 and (somewhat surprisingly) still exists today. The meal replacement diet involves eating up to four high-protein cookies in place of breakfast, lunch and snacks. Sadly, it’s not as fun as it sounds; the cookies aren’t as tasty as proper biscuits, plus it's hard to get enough fruit, vegetables and other nutrients into your diet when you're mainly eating processed cookies. You may lose weight, but you won't have a balanced, healthy diet.

16. The baby food diet

The baby food diet hit the headlines in 2010 when it was linked to a celebrity trainer and a host of Hollywood stars. The diet plan was rumoured to involve eating 14 portions of puréed fruit and vegetables throughout the day, plus an 'adult' meal in the evening. You may lose weight quickly on this low-calorie diet, but you won't get all of the nutrients an adult needs.

15. The carnivore diet

The carnivore diet, which involves cutting out all plant products and only eating animal produce (red and white meat, fish, eggs and dairy) has steadily gained popularity in the 2020s. Hugh Jackman reportedly used the diet to get in shape for his role in Wolverine, while other celebrities linked to the diet have included Heidi Montag, Joe Rogan and James Blunt – the latter of whom reportedly developed scurvy after two months on an all-meat diet. This eating plan misses out important vitamins and nutrients from fruits and vegetables, as well as being dangerously low in fibre. These factors could lead to a higher risk of colon cancer, type 2 diabetes and cardiovascular disease.

14. The Lion Diet

The lion diet, a massive TikTok trend in 2023, takes the carnivore diet a step further – allowing only red meat, salt and water. The elimination diet, which claims to help heal the gut, body and brain, was originally created by podcaster Mikhaila Fuller, who says following it has helped to ease her many health problems. Experts warn against it, though, saying the diet lacks nutrients and fibre, is high in saturated fat and could lead to health problems including high cholesterol and haemorrhoids.

13. Applying goose grease

Liquid diets have caught on time and time again throughout history. One particularly unpleasant example is 1976's Last Chance Diet, which involved drinking a product called Prolinn. This ‘predigested liquid protein’ was made of animal byproducts, such as hide and tendons, and was supposed to be drunk a few times a day in small amounts. The product was taken off the market after being connected with several deaths.

12. The Sleeping Beauty Diet

It's believed that the origins of the bizarre and dangerous Sleeping Beauty Diet – which, in the simplest terms, involves sleeping to avoid eating – can be traced to Jacqueline Susann's 1960s bestseller Valley of the Dolls, which saw one character going to a Swiss sleep clinic in order to lose weight. Worryingly, taking sleeping tablets and sleeping a lot to avoid hunger and eating has been a trend in more recent years, too. It's a diet that was reportedly used by Elvis Presley, who even went as far as being put into an induced coma to lose weight.

11. The Last Chance Diet

Liquid diets have caught on time and time again throughout history. One particularly unpleasant example is 1976's Last Chance Diet, which involved drinking a product called Prolinn. This ‘predigested liquid protein’ was made of animal byproducts, such as hide and tendons, and was supposed to be drunk a few times a day in small amounts. The product was taken off the market after being connected with several deaths.

10. The tapeworm diet

It sounds like the stuff of horror fiction – but back in the early 1900s, people actually wanted a tapeworm put inside them to gobble up calories. Tapeworms, sold in pill form for diet purposes, were a massive craze, which is especially terrifying when you consider that baby tapeworms can grow up to 25 feet (7.6m) long. The side effects are more than just being deprived of nutrients; the US government banned the pills from sale after people started developing side effects like seizures, meningitis and cysts on the brain.

9. Smoke to 'reduce'

If ever there was a diet that should come with a health warning, it's this. In 1928, American cigarette brand Lucky Strike coined the slogan 'reach for a Lucky instead of a sweet', encouraging people to suppress their hunger pangs by smoking instead (this photo shows a surviving billboard from the 1930s). It went on to advise people to 'avoid harmful methods to reduce' and enjoy the delicious toasted flavour of Luckies as 'a delightful alternative to the things that make you fat' instead. Oh, the benefits of hindsight…

8. Amphetamines

During the 1960s, taking stimulants to speed up metabolism was prevalent – and in 1970-71 it was revealed that 5% of adults in the US had used amphetamines in the past 12 months. Diet clinics, where poorly qualified 'diet doctors' dished out the highly addictive medication like sweets, were everywhere. Side effects of using amphetamines include anxiety, headaches and a dry mouth.

7. Beverley Hills Diet

A fad diet devised by author Judy Mazel in the 1980s, the Beverley Hills eating plan allows only fruit for the first 10 days, carbohydrates from day 11 and, finally, protein on day 19. It’s based on the unscientific notion that blending certain foods inhibits digestion, and that undigested food is what makes people gain fat. It’s complete nonsense and potentially dangerous too, offering a lack of nutrients and just 800-1,000 calories a day.

6. The air diet

In 2010, European women’s magazine Grazia published an article in France advocating the ridiculous notion of not eating food, but smelling it instead. Supposedly a diet all the stars were dabbling in at the time, it involved preparing food just to revel in its fragrance, in the hope that it would satisfy the urge to eat. It was so outrageous that some suggested it had to be a joke – especially as it was accompanied by a recipe for water soup, consisting of just water and salt.

5. Woman’s Own diets

Dieting and weight loss for women were big business after the Second World War, as the desired silhouette shifted to a slimmer shape. Women’s magazines were enthusiastic proponents of these diets, including the popular Woman’s Own, which recommended a whopping 40 different diets from 1966 to 1970 (many of which contradicted each other). One such diet involved eating between 350 to 900 calories each day in the form of small tomatoes and up to six hard-boiled eggs – to be eaten only when hungry.

4. The starvation diet

We've all heard about calorie counting, but this restrictive diet was around long before calories were a thing. Written by Italian nobleman Luigi Cornaro in 1558, La Vita Sobra (The Sober Life) advocated extreme starvation as a way to lose weight and boost health. The author himself lost weight and reportedly lived to the age of 102 by eating just 12oz (342g) of food and drinking 14fl oz (400ml) of wine per day. Evidence suggests mice live longer when fed starvation rations, but it's not been proven in humans.

3. The Kimkins diet

Heidi Kimberly 'Kimmer' Diaz faked a 200lb (91kg) weight loss and made money from this scam diet plan. The Kimkins diet promotes an extremely low-carb regimen and advocates eating as few as 500 calories a day – as well as taking laxatives. The dangerous diet attracted attention in 2007 when it was featured in Woman’s World magazine, which subsequently apologised.

2. Diet pills with arsenic

Most nutritionists agree that diet pills are not a healthy way to manage your weight. Popping pills to speed up metabolism became a diet trend back in the 19th century. However, shockingly, many of these seemingly miraculous tablets contained small amounts of strychnine and arsenic, which consumers might not have been aware of. Chronic arsenic poisoning leads to cancer and liver disease.

1. Eating cotton wool balls

This deadly trend, which gained attention in 2013, is more of an eating disorder than a diet plan; it sees those desperate to lose weight consuming cotton balls soaked in juice. As well as providing absolutely no nutritional value, cotton balls can easily cause choking or become lodged, leading to ulcers, gangrene and intestinal bleeding.

Now discover the world's deadliest foods

Last updated by Laura Ellis.