The top 5 worst fad diets of all time

Posted by Dayne Hudson in Weight Loss

Estimated reading time: 8mins

The top 5 worst fad diets of all time
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5. The Paleo Diet

This fallacy says if we eat as cavemen did, we’ll be healthier.

But there’s no hardcore scientific evidence to back this up – only evidence to disprove it.

What's allowed:

  • Meat
  • Eggs
  • Poultry
  • Fish
  • Fruit
  • Vegetables (except tomatoes, potatoes, & eggplants)
  • Nuts
  • Seeds

What's disallowed:

  • Grains and legumes
  • Milk (and milk products)
  • Refined/added sugars
  • High omega-6, refined or hydrogenated vegetable oils
  • Nightshade vegetables such as tomatoes, potatoes, & eggplant
  • Added salt
  • Coffee & alcohol

Paleo diet proponents blame agriculture and carbohydrates for the rise in poor health and obesity and thus ask us to steer clear of it all.

But this totally ignores how the world has changed. One notable difference is technology.

A review in 2021 reveals many of us are moving less, which we know all too well.

Other studies show we burn 142 calories less at work than we did in the 60s.

And if you factor that in with a roughly 445 daily calorieincrease, we've had since then, we're looking at a 587-calorie surplus.

But there’s an even bigger problem…

They’re wrong about what they THOUGHT cavemen ate

Starch granules have been found on paleo tools from Mozambique, believed to have started at least 105,000 years ago.

Other research has also found starch granules on the surfaces of grinding tools from as far as north-eastern Europe to the central Mediterranean.

What's more, plant food processing, and maybe even the production of flour was across Europe from at least 30,000 years ago.

So, the claims cavemen didn't eat carbohydrates aren't supported by research.

What's more, there are actually next to zero accurate records of what they DID eat. There was never research conducted into this.

But where there is research is that whole grain and legume consumption can help us with improved blood lipid profile, glucose control, reduced risk of stroke & coronary heart disease, and reduction of inflammation.

Then there's the claim from paleo followers that grains cause inflammation.

But research shows that 3-4 servings per day of either refined or whole grains reveal no inflammatory effects.

Paleo diet creators didn’t actually know what caveman used to eat...
Paleo diet creators didn’t actually know what caveman used to eat...

Carbohydrates can be healthy

Research conducted by Dan Buettner uncovered what is called "the Blue Zones." These were the places on earth where people lived the longest due to their diets and lifestyles.

Mr Buettner researched what they ate, and surprise surprise – carbohydrates were the most consumed macronutrient.

This of course flies in the face of the paleo diet guidelines and recommendations.

Also, 3 of the 5 blue zones regularly drink coffee, and 4 of the 5-drink alcohol regularly.

And ALL 5 consume grains and legumes.

And last but not least, none of them specifically follow the paleo diet.

The paleo diet is not sustainable for the majority of people today, so if you’re thinking about following it, don’t.

4. The Ketogenic diet

Similar to the Paleo diet, the ketogenic diet also demands a very limited amount of carbohydrates:

  • High protein
  • High fats
  • Low carbohydrates (20-50 grams per day).

So why low carbohydrates?

Well, some people still think that because eating carbohydrates causes an insulin spike, it creates instant fat storage.

Scientists refer to this as the "carbohydrate-insulin hypothesis of obesity", which has been debunked multiple times.

But. It’s. A. Fallacy.

You can send 2000 calories worth of energy to your fat cells with an insulin spike, but if you burn 2500 calories a day, you can't gain weight.

So spiking insulin isn't the problem here. It’s eating MORE calories than you burn that’s the issue. Simple.

Weight loss is governed by a calorie deficit only, not the foods (or carbohydrates) that make up that deficit.

If you understand this, you’ll be ahead of lots of people.

And there’s another problem…

Carbohydrates can be healthy.
Carbohydrates can be healthy.

People can’t stick to a ketogenic diet

Adherence to a ketogenic diet causes problems for many people. One review concluded:

"Adherence appeared to be particularly problematic for those studies who set out to achieve a very low-carbohydrate diet (<50 g carbohydrate per day), with only one out of the six trials that prescribed a very low carbohydrate diet being able to achieve this target as an average value."

The other issue is the hindrance of performance. Research shows that anaerobic exercises like sprinting or weightlifting are negatively affected by the low levels of carbohydrates eaten on a ketogenic diet.

So, if sprinting is your thing, or weightlifting (as it may be for lots of people reading this) you're putting yourself at a disadvantage.

Do yourself a favour – forget about this diet entirely.

3. The Cookie Diet

A doctor in America came to market with this stupid diet years ago.

You buy his cookies which contain protein and fibre, and that’s what you eat the most at the start of the diet.

Now, I love cookies as much as the next person, but not pretend ones that don’t taste like the real thing.

And I certainly don’t want to eat them at every meal.

There’s nothing magical about them, but they’ll tell you there is.

Do you know what’s better?

EATING your protein and fibre every meal: chicken and greens, fish and salad, eggs and fruit – and then eating REAL cookies when you feel like it.

That’s much more sustainable.

2. The Apple Cider Vinegar diet

The Apple Cider Vinegar diet advocates taking 1-2 tablespoons (15-30ml) of Apple Cider Vinegar per day mixed with water for weight loss.

The dose should be spread out over a 24-hour period, potentially consuming the diluted dose directly before meals.

So, does it work?

Of course not.

A huge review examined the diet’s weight-loss claims and found nothing of significance to report.

We’re also told the diet is good for our health, but there’s no evidence to back this up, either.

Another one to steer clear of.

1. The Air Diet.

I’m not even making this up.

A diet from France, it’s also known as the virtual eating diet.

Followers sit down and PRETEND to eat a meal they would like.

They imagine smelling it, chewing it, and trying to convince themselves they’ve eaten it.

But all they can ACTUALLY eat is a salt and water soup concoction.

So, they miss out on essential nutrients and basically just destroy their health.

But it’s a thing. Somehow.

Here you go, take a big mouthful of this! I cooked it fresh!
Here you go, take a big mouthful of this! I cooked it fresh!

The bottom line on the worst fad diets

So, there are some of the worst fad diets of all time. None of them are grounded in scientific truth, just the spreading of misleading weight loss theories that enough people decide to try.

The paleo diet and ketogenic diets are based on the fallacy that carbohydrates make us gain weight, and the cookie diet is an unsustainable unnecessary approach to fat loss. The apple cider vinegar diet is not supported by science, whilst the air diet is downright stupid.

Stick to a high protein diet, with carbs and fat, and enjoy everything in moderation.


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group of product images for proteins
group of product images for proteins