In 2023 I decided to change my life. I wanted to lose weight so I could move better, and feel better. It was the first time in my life I'd actually made any real effort to learn about food and nutrition.

As part of that learning, I started to listen to podcasts featuring people like Professor Tim Spector, Dr Michael Mosley and Dr Chris van Tulleken. I learnt about the importance of movement and sleep, and how these can drastically improve your health.

And I learnt a lot about food, more specifically, what foods to avoid and why. I was shocked to learn that foods I had previously believed were healthy, actually are no better than their unhealthy alternatives.

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Most of these foods that are supposedly healthy I discovered were in fact ultra-processed, and this in itself was a new term I discovered. So what is ultra-processed food? For the latest health and Covid news, sign up to our newsletter here

Dr Chris van Tulleken, who researches and writes about ultra-processed foods, describes it in a very simple way. Ultra-processed food, according to Dr Tulleken "boils down to if it's wrapped in plastic and it contains at least one ingredient that you don't typically find in a domestic kitchen, then it's ultra-processed food."

But processed food isn't necessarily all bad, as we as humans have been processing food since the beginning of time. And there are some foods I absolutely cannot or will not give up - like chocolate.

However learning about ultra-processed food taught me that many foods I once viewed as 'healthy alternatives' simply aren't. Just to caveat this with saying I do not believe in cutting any food out of your diet completely, as I truly believe it is possible to have a balanced diet and allow yourself to enjoy a treat. This is rather to show that foods we often believe are healthy alternatives aren't always as they seem.

These are the five foods I once thought were healthy that I have stopped eating:

1. 'Low calorie' snack bars

Cereal bars along with other low calorie snack bars such as mini "fibre" brownies, or yoghurt coated crisp bars are often marketed to us as a healthier alternative to chocolate. But just like chocolate, most of these bars actually contain a high amount of sugar, and other ingredients like sweeteners if they have been stripped of sugar.

Looking at the ingredients in a very popular low calorie chocolate brownie, which are just 90 calories each, there are around 15 ingredients, some traditional ones like flour, but mostly things you won't find in a domestic kitchen, like raising agents, thickeners (xanthan gum) and humectant (glycerol.) These are often added to make up for the loss of fat or sugar in a food.

If you were to make a chocolate brownie at home, it should take only six ingredients; dark chocolate, butter, flour, eggs, cocoa powder and sugar. Dr Tulleken warns that there is a growing amount of research that shows the "inherent dangers in consuming complex mixtures of substances that humans have never encountered before". Tim Spector claims there is also growing evidence that UPFs like these are driving obesity in the western world.

In my experience, I allowed these low calorie snacks to be part of my daily routine because they are low calorie but as evidence is starting to suggest, there are no real health benefits to this.

2. Fruity yoghurts

Once again, a fruity yoghurt is often marketed as a healthy snack, and many even claim to be good for gut health, but most on our supermarket shelves are far from the natural form of milk and added bacteria. Looking at a popular brand that is famed for "gut health", ingredients (of which there are 12) include things like stabilisers, sweeteners, and regulators.

Compare this to an all natural kefir, which is milk with live bacterial cultures and yeasts - an actual great gut health drink. There is growing evidence that sweeteners have distinct effects on our gut, so it is clearly counter productive to consume a yoghurt that is marketed for "gut health" when it contains the very ingredient that scientists have raised concerns about.

3. Alternatives to butter

Like with the above two examples, I always used to opt for a vegetable spread instead of a typical butter because I believed the lower fat option was the healthiest. But many of these products contain emulsifiers. A study published in the British Medical Journal found that a high intake of emulsifiers is linked to increased risk of heart disease. I now opt for a bog-standard butter, where the only ingredient is milk, instead.

4. Orange juice

It is made of fruit, how bad can it be? And while the sugar in orange juice is natural, it is still very high. According to the British Heart Foundation, one small 150ml glass of orange juice is the equivalent of three oranges, however it won't have the same fibre content as if you were to eat them whole.

There are 39 grams of sugar in a 12 oz Coca-Cola can. According to the USDA, there is 2.6g of sugar per 1oz of orange juice - meaning a 12oz glass of orange juice has 31.2 oz of sugar in it, just over seven grams less than a can of coke.

5. Smoothies

This leads on naturally to smoothies. I once treated smoothies as a great way of getting a load of fruit in my system. And of course, given the choice of a smoothie or a can of coke, a smoothie is the better option.

However, the process of blending fruit means we break down the plant cell walls and expose the natural sugars within - this effectively turns them into "free sugars", which we are often told to avoid or at least reduce.