Why everything you know about healthy eating is wrong

Food and diet stories are always popular – but many of the claims, including some widely held beliefs, aren’t backed up by good-quality evidence. Nutritionist Hannah Elliott debunks 11 of the most popular food and diet myths.

Myth 1 – “Natural” sweeteners like honey are healthier than sugar

A jar of acacia honey on a wooden table, next to acacia blossoms 

Natural sugars like honey, and syrups such as agave syrup, rice syrup, malt syrup, and molasses, are often believed to be healthier than white sugar

In fact, honey, syrups, anything that ends in ‘ose’, and cane sugar (including unrefined cane sugar) are still sugar – regardless of how natural and healthy they sound. They will all provide around the same amount of energy.

A high sugar diet is associated with a high energy intake, which over time can lead to weight gain and obesity. Any additional nutrients that come with less refined sugars will provide a minimal contribution to the diet – they aren’t a reason to include these foods in the diet and it’s not a good idea to eat more sugar because of the nutrients that might come with it.  

Myth 2 – Gluten-free grains are healthier than wholegrains

Half a coconut on a table with leaves, coconut oil and coconut flour

Gluten free grains like buckwheat or quinoa and ancient grains like amaranth have recently gained massive popularity. They are often reported to be healthier than normal grains as they do not contain gluten.

But unless you are intolerant of gluten, and have been advised to avoid it by a health professional, then there is no real need to avoid foods that contain it. So rather than focusing on this, try to ensure you are having healthy grains by choosing wholegrains (including oats and brown rice) and products made from them (such as wholegrain bread, wholegrain breakfast cereals and whole-wheat pasta) as they contain more fibre.

As well as choosing wholegrains, it’s important to check the food label of products made with wholegrains as while they will be a better source of fibre compared to standard versions, they can still be high in saturated fat, salt and sugar.

And if you fancy trying buckwheat, quinoa or amaranth, there’s nothing wrong with this – having a variety of different foods in your diet is good as it keeps things interesting.

Myth 3 – Coconut oil is healthy

Half a coconut on a table with leaves, coconut oil and coconut flour

Coconut oil seems to be everywhere in the media, recipes and products for sale. It’s often reported to be a healthy fat, and there are claims that it can improve an array of health conditions, including coronary heart disease.

In fact, coconut oil contains about 85 per cent saturated fats. A high intake of saturated fat can increase the amount of cholesterol in your blood, increasing your risk of developing coronary heart disease. Although there have been some studies looking at the effect of coconut oil on blood cholesterol, these are not good quality – either because they are short-term, based on small numbers of participants or based on animals. 

If you like the taste of coconut oil then it’s fine to use a little now and then – advice that also applies to other saturated fats like butter and ghee. But for everyday use, the consensus of the evidence tells us that it’s best to replace saturated fats with unsaturated fats like olive, rapeseed or sunflower oil and the spreads made from them. 

Myth 4 – Eggs are bad for your heart

Poached eggs, spinach and watercress on wholemeal toast

Eggs are a source of cholesterol, and so many people think they should be avoided to reduce risk of heart disease. 

The advice on eggs has changed over time, so it is not surprising that this is a source of confusion. Eggs can be included as part of a balanced diet. 

Early studies made the assumption that cholesterol in egg yolks was the reason behind study participants’ increased blood cholesterol levels. However, further investigation showed that it was not eggs but saturated fats that had more of an effect on blood cholesterol levels. 

For most people, the way you cook eggs or the foods you serve alongside are more important than the eggs themselves. Poaching or boiling is healthier than frying in bacon fat or scrambling with butter.

Myth 5 – Granola is a healthy breakfast

 A jar of granola on a kitchen table with milk

While granola does contain wholegrains, it is usually a high sugar choice due to the addition of honey, syrups or sugar in contrast to oat-based breakfasts, like porridge and some muesli. Granola is also likely to contain added fat, so it’s usually higher in energy – something to be aware of if you’re trying to lose weight. What’s more, the fat that’s used might be palm oil, which like coconut oil (see Myth 1) is a type of saturated fat.

Alongside this, it’s easy to consume a bigger portion than stated on the packaging. If granola is the only option, limit your portion size by weighing it out or using a measure. You can also mix it with some low-sugar wholegrain cereal so you still get the taste, but less of the sugar. Better choices would be porridge topped with fresh or dried fruit for natural sweetness, or no added sugar muesli.

Myth 6 – Juicing fruit and veg is the healthiest way to eat them

 A glass of green juice, surrounded by broccoli, brussel sprouts, fresh parsley and cabbage

Juicing is big business, and some people see it as the easiest way of getting all your five portions of fruit and vegetables in one go. But in fact, while juices will be more nutritious than other soft drinks, they can only count as one portion of your 5-a-day

When fruit and vegetables are juiced, the sugars within them are released as free sugars, which is the type of sugar we need to cut down on. Choosing unsweetened fruit juice can count towards one of your five a day but keep the portion to 150ml, once a day. It’s also best to drink it with a meal to help protect your teeth.

 Myth 7 – Pickled and fermented foods are great for your health

 Jars of pickled and fermented vegetables

Pickled foods are one of the biggest food trends for 2016. Fermentation has been used for thousands of years as a preservation method for fruit and vegetables, and is used to make bread, yoghurt, wine and beer. Recently some fermented products have grown in popularity because of reported benefits for our digestive system. 

The big drawback is that pickling fruit and vegetables will usually require the addition of salt and sugar. While pickled foods can be part of a balanced diet, due to their high salt content they should be eaten in small amounts. Having too much salt on a regular basis can lead to high blood pressure, a risk factor for coronary heart disease and stroke.

Myth 8 – We need to “detox” regularly

Hands holding a mug of 'detox' tea

There’s a popular belief that having a regular “detox” can help release toxins from the body and aid weight loss. This can mean buying special detox tablets, teas and smoothies, cutting out alcohol or fasting for a short period of time.

The truth is that our bodies are well adapted to take toxins out of the body through the normal function of the liver, kidneys and lungs. If these aren’t working properly, you would feel very ill. A detox where you cut out unhealthy food and drinks for a few days and eat more fruit and veg may well make you feel better, but if you then return to your old ways it will do little to improve your health. 

It may not sound as glamorous, but eating a balanced diet, including at least five portions of fruit and vegetables a day, doing regular exercise, not smoking, getting a good night’s sleep and limiting your alcohol intake, will bring have sustained benefits and, combined with some regular physical activity, should help you to lose weight in a safe and gradual manner if you need to. 

  •   See more information on detox 

Myth 9 – Red meat is always bad for your heart

Half a coconut on a table with leaves, coconut oil and coconut flour

Research has linked red meat and processed meat to an increased risk of certain conditions, such as bowel cancer, so some people think they have to cut it out of their diet to be heart-healthy.

Red meat is a good source of protein and provides vitamins and minerals including iron, so it's not all bad. However, studies have linked high intakes of red and processed meat with an increased risk of cardiovascular disease. It’s recommended that people who eat a lot of red meat (more than 90g a day) should cut down to 70g a day, because of links with bowel cancer. So you don’t necessarily have to give up red meat completely, but you might need to cut down if you eat a lot.

When it comes to heart health, the main thing to think about with red meat is the amount of saturated fat that it contains. Choose lean cuts of red meat or extra-lean mince and trim off any excess before cooking. When it comes to processed meats, you need to look out for the salt content as well as the saturated fat, so make sure you read the food labels.

Processed meats like bacon and ham will always have salt added as part of the curing process. Compare different brands by using the ‘per 100g’ information on the back of pack and eat them every now and then rather than as everyday choices.

Myth 10 – All fats are bad for you 

Sliced avocado on a piece of wholegrain toast

When it comes to fats as part of a heart healthy diet, it’s not always as black and white you might sometimes think. While fat reduction was recommended in the past, on average we are now meeting dietary recommendations about the total amount of fat in our diet. 

But if you are trying to lose weight, then you might need to cut down to reduce your energy intake, as fat is the most energy dense nutrient. Overall though, we should be paying more attention to the types of fat we eat, as average intakes of saturated fat (such as butter, ghee, coconut oil and lard) are still above of the amounts recommended, which equate to around 30g a day for men and 20g for women. 

It's good to replace saturated fats with unsaturated fats as this has been shown to help lower LDL (bad) cholesterol levels. Use unsaturated oils and spreads, eat a portion of oily fish each week and swap snacks high in saturated fat for healthier options like unsalted nuts and seeds or avocado on wholegrain toast.

Myth 11 – Eating an alkaline diet is better for your health

 A woman dressed in red is holding a wooden bowl of almonds, just about to eat one

The aim of an alkaline diet is to re-establish the body’s pH (alkalinity/acidity) balance by avoiding foods that will ‘make your body more acidic’ like caffeine, alcohol, dairy, sugar, gluten, wheat and processed foods, and eating foods that will ‘make your body more alkaline’ like barley, almonds, oil, herbal teas, fruit and vegetables.

The diet's claimed benefits are that it helps to lose weight and can ease arthritis, prevent cancer and kidney stones, reduce risk of type 2 diabetes and improve heart health.

Many of the foods recommended as being alkaline are also healthy choices, and there's no harm in cutting down on alcohol and processed foods high in saturated fat, salt and sugars. However, there is no scientific basis to this diet.

The human body is well equipped to maintain a steady pH in the blood, and many of the membranes in our body require an acidic pH to protect us and to help us digest food. Cancer Research UK describes the idea that an alkaline diet will reduce your cancer risk as “biological nonsense.” As with most fads, the alkaline diet is unlikely to provide a long-term solution if you want to lose weight.

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