Fad diets

There are lots of reasons for wanting to change your diet. However, this should not be at a cost to your health, your relationship with food or your wallet.

Tempting though the endless range of ‘quick fix’ and ‘miracle’ options may be, the promises they make of rapid results for minimum effort are often unrealistic and unsustainable.

Unfortunately, there are no ‘magic' diets. Most fad diets are associated with some form of nutrition or health risk. A fad diet offers a short-term solution to a long-term problem. 

What is a fad diet?

A fad diet is a plan that promises results (such as fast weight loss) without robust scientific evidence to support its claims. Popular ones include plans where you eat a very limited diet with few foods allowed or an unusual combination of foods. The diet may only allow you to eat at certain times or involve fasting. Fad diets often consist of expensive and unnecessary food products, ingredients and/or supplements such as pills and powders.

Where’s the harm in fad diets?

Many fad diets will lead to initial results that may be short lived or have unintended consequences. For example, cutting out carbohydrates can mean a drop in your fibre intake, leading to gut problems such as constipation and bloating. Rapid weight loss may involve the loss of lean muscle and fluid, not just body fat.

Often these diets cannot be followed long term because people become fed up with the strict rules and restrictions, and they may also pose a risk to health.

When food groups are demonised, internal cues around hunger and fullness are ignored and you’re having to follow an exhausting list of rules. This can negatively affect your relationship with food. It can lead to feelings of failure rather than developing the skills and confidence to manage your diet in a healthy manner.

How to tell the diet fact from the fiction

Beware! Stay away from diets that:

• Promise a magic bullet to lose weight without having to change your lifestyle in any way. These include diet pills, lotions, wearables such as bracelets or sweat suits.
• Promise rapid weight loss of more than 1kg (2lb) of body fat a week such as keto or fasting.
• Recommend magical fat-burning effects of foods such as the grapefruit diet or hidden ingredients in foods (caffeine/coffee diet) or alleged fat burning substances, such as green tea extract or raspberry ketones.
• Promote the avoidance or severe limitation of a whole food group. This could be dairy products, carbohydrates, or a staple food such as wheat. Examples include low carbohydrate diets, the ‘carnivore diet’ or ‘paleo diet’.
• Suggest substituting everyday foods or food groups for expensive doses of supplements, expensive ingredients, or special products such as the ‘bulletproof diet’.
• Promote eating one type of food (mono diet) e.g. ‘cabbage soup diet’, ‘chocolate diet’ or ‘egg diet’, or avoiding all cooked foods (‘raw food diet’).
• Recommend eating foods only in particular combinations based on your genetic type or blood group.
• Suggest being overweight is related to a food allergy or a yeast infection.
• Recommend “detoxing” or avoiding foods in certain combinations such as fruit with meals.
• Are based on claims that we can survive without food or having liquid meals only.
• Offer no supporting evidence apart from personal success stories.
• Focus only on your appearance rather than on health benefits.
• Are selling you products or supplements.
• Recommend eating non-food items such as cotton wool.
• Have recommendations based on a single study, testimonials or unrealistic amounts of a food e.g. chilli.
• Recommend the same diet for everyone without accounting for specific needs.
• Are based on a secret that doctors are yet to discover or don’t want you to know.
• Imply that food can change body chemistry.
• Misinterpret medical tests or how the body works such as the ‘alkaline diet’ or the ‘collagen diet’.
• Are labelled as ‘wellness’ but are about strictly controlling food e.g. clean eating.

Remember, if it sounds too good to be true – it probably is!

Make sure people giving diet advice are qualified

Social media, filters and photoshopped images can make us believe that influencers and celebrities are picture perfect all the time. However, this is unrealistic and can make us feel bad about ourselves and our own ‘imperfections’. Remember, just because someone is famous, or has a following, does not make them an expert in nutrition.

Many people, on social media and in real life, claim to be experts in nutrition yet may have limited knowledge and offer no protection to the public. You should be wary of unqualified practitioners who may be offering unproven techniques to diagnose and treat nutritional problems including:

• Iridology, kinesiology, craniosacral therapy, hair mineral analysis, face reading, tongue reading, colonic irrigation and magnetic therapy.

Dietitians have legally recognised qualifications and are independently regulated health professionals with a protected title. They will be able to guide you through the mountain of diet information available and give you safe, unbiased, evidence-based advice. Ask your GP to refer you to a dietitian or find a freelance dietitian.

Top tips

• Dietitians will be able to help you know if diet information is safe and based on evidence.
• The best way to maintain a healthy weight is to consider your diet as a whole.
• Make healthier choices where possible and include variety and balance.
• Listen to your body's hunger and fullness cues.
• Be aware of portion sizes and consider activity levels.