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What are the best weight loss diets?

The issue of dieting – particularly when focused on weight loss – can be a contentious subject, largely because there is no universally agreed upon method to lose weight in a safe and healthy way. The way you diet will be determined by the reasons behind the choice – whether you’re doing it for a specific goal, to tackle a health problem or for lifestyle reasons. Here we discuss the pros and cons of some of the most popular modern weight loss diets, and what you should bear in mind when considering any of them.

Intermittent fasting

Intermittent fasting (otherwise known as the 5:2 diet) allows you to essentially eat what you want for five days a week, and then fast for the other two. For this reason, it is generally considered to be easier to follow in comparison to more complicated calorie-controlled diets which can also often require you to memorise complex food charts. In terms of weight loss results, intermittent fasting generally produces similar results to the Mediterranean diet. On the downside however, the fasting portion of the week can lead to side effects such as irritability, fainting, dizziness and low energy.

Low-carb v mod-carb

Another popular way to diet is by controlling the amount of carbohydrates you eat, with everything from high to moderate, low and no carb variants. This can often be a good idea simply because many carbohydrates we typically eat are processed, and processed food is typically linked with weight gain – but carbs are not inherently fatty. There is also evidence that carbs stimulate insulin release, which is itself an appetite suppressant, so they could even be good for your diet. A recent study suggested that a low-carb diet can be an effective way to lose weight, as long as people are also eating a healthy diet with plenty of vegetables and smaller portions.

Plant-based: Healthy or not?

Like other diets aimed at cutting out certain food groups, a plant-based diet can be healthier purely because it tends to mean cutting out processed foods entirely. This combined with an increase in the intake of fresh fruits and vegetables is bound to lead to weight loss, but if not combined with a more sophisticated nutrition programme it can lead to serious deficiencies in nutrients like iron, essential fats and oils. With a good understanding of what makes up a healthy, balanced vegan diet, you should be able to get all the necessary nutrients that you need.

An exclusively plant-based diet that isn’t followed properly could mean missing out on essential nutrients such as calcium, iron and vitamin B12.

Meal replacement therapy

In essence, meal replacement treatments involve literally replacing or supplementing daily meals with low-calorie alternatives that satisfy and suppress appetite without adding many extra calories or fats. This often takes the form of bars or shakes and can be a great way to wean yourself off fatty foods in the short term. It’s also easier on will power in the long term, as you won’t feel like you’re starving. Another advantage of meal replacement therapy is that it can be extremely convenient, with products often taking the guesswork away from portion control and calorie counting. The downside to this is that an over-reliance on pre-prepared portions does very little to help educate people about their eating habits, which can mean there’s an increased risk of regaining any weight lost once you come off the diet. However, this method again can keep you from getting essential nutrients such as fats or good calories.

Ketogenic diets

The Ketogenic or Keto diet has one major positive in that it doesn’t demonise fats in the same way as other diets such as Atkins. It’s also good for the average person who doesn’t take part in high-intensity exercise because its low carb rules don’t fill you full of slow-burn energy that you won’t work off. It has also been linked with positive effects on heart disease, Alzheimer’s disease and type 2 diabetes thanks to its emphasis on oily foods and Omega 3. However, like any diet that aims to cut out carbs, there is the danger that it can lead to a shortage of sugars, decreased testosterone and muscle wastage.

In the end, only you can know which diet best suits your lifestyle and level of activity – and no amount of advice can make that decision for you. However, if you do plan on making drastic changes to your diet you should always consult a medical professional first.

If you’re looking for help with weight loss, there are a number of weight loss apps on the market.

For more information on dieting and weight loss, call +44 (0) 20 7467 5470 or email

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