Is cutting out whole food groups ever a good idea?

It may seem like a good idea to cut certain food groups from our diets, but it is safe to do so?

Low-fat diets

High levels of fat in the body lead to raised cholesterol levels, increasing the risk of heart disease. Many people are eager to cut fat out of their diets to try and shift a few pounds. However, cutting fat completely from the diet can do more harm than good, as dietary fat is essential to keep the body healthy.

Fat is a major source of energy and plays a wide range of roles in the body such as synthesising hormones, helping the absorption of key vitamins and helping to maintain body temperature. Knowing the difference between saturated fats (found in butter, cheeses, red meat and other animal-based foods) and unsaturated fats (found in oily fish, vegetable-based oils and nuts) is important when deciding which fats to cut out. Unsaturated fats protect the heart by maintaining healthy cholesterol levels and providing essential fatty acids, while saturated fats can increase the risk of heart damage and disease by raising cholesterol levels. So whilst it might be beneficial to reduce the intake of certain types of fats, cutting them out altogether may not be advisable.

Low carb diets

Another popular food type that many people try to reduce or cut from their diet is carbohydrates. Carbohydrates are the body’s main source of energy and are also a source of vitamins and minerals. There are 3 different types of carbohydrates found in food: sugar, starch and fibre. The Atkins and ketogenic diets both encourage the elimination of carbohydrates in the diet for the body to produce small fuel molecules called ‘ketones’. These are produced by the liver from fat used as an alternative fuel for the body when sugar is in short supply. Eating carbohydrates have a big impact on blood sugar and insulin levels and restricting carbohydrates helps to lower sugar levels and insulin needs. High sugar levels play a part in almost all chronic diseases such as type 2 diabetes, dementia, cancer and cardiovascular disease.

Although too much sugar is bad for health, sugar is vital for the normal functioning of the body. Carbohydrates contain essential vitamins and minerals including calcium, vitamin C and iron as well as dietary fibre. Because carbohydrates can interfere with hormone production, in some women following a low carbohydrate diet can cause damaging side effects. Cutting carbohydrates from the diet can interrupt a woman’s menstrual cycle, disrupt the production of thyroid hormones over time, leading to fatigue, poor concentration and irritability. Although some people may see fast weight loss results upon following a ketogenic diet, cutting all carbohydrates out can be difficult to uphold over a long period which can lead to people regaining the weight they have lost. We should all aim to reduce the amount of free sugar in our diet and should base meals on starchy carbs, particularly those high in fibre.

Cutting out meat and dairy

Over recent years many people have switched to a plant-based diet thanks to the health and environmental benefits a vegan lifestyle can bring. Plant-based eating is associated with sustainable weight management, lowered cholesterol levels as well as a reduced risk of diabetes and heart disease.

The World Health Organisation (WHO) ranks processed meat alongside smoking as a major cause of cancer [1]. Despite the popular myth, meat isn’t the only way to get protein. There are many different sources of plant-based proteins including tofu, tempeh, lentils, nuts and chia seeds.

Restrictive Diets

Plant-based proteins are a healthier choice in comparison to meat because they contain no cholesterol and are low in saturated fats. Dairy and meat products contain a large number of saturated fats which increase the risk of heart disease. Reducing the number of saturated fats from your diet helps to improve health tremendously, especially when it comes to cardiovascular health.

Cutting out all animal products can however lead to deficiencies in key vitamins and minerals. Vitamin B12 is an important vitamin for a healthy nervous system and DNA synthesis. Vegans struggle to get enough vitamin B12 through food as it is only found in animal products. As this vitamin is found almost exclusively in animal-based products, those who follow a vegan diet are at risk of B12 deficiency so checking their B12 levels is very important. Supplementing vitamin B12 can help to raise low levels.

Vitamin D levels should also be monitored. The flesh of fatty fish such as mackerel, tuna and salmon as well as fish liver oils are among the best sources of dietary vitamin D and small amounts of vitamin D can also be found in egg yolks, beef liver and cheese. Because vegans eat only plant-based foods it can be difficult to get the right of vitamin D from diet alone, however, it is difficult for anyone to get the required amount of vitamin D from diet or sunshine alone in the UK so supplementing vitamin D can help to improve levels.

Check yourself!

Before making any major dietary changes such as cutting out certain food groups it is important to understand how this can affect your health. Because cutting certain food types out of your diet may lead to deficiencies in essential vitamins and minerals, it is important to check your health status when changing your diet. Our range of Diet and Lifestyle Checksare perfectly suited to check how your choices are affecting your health. Get insights into your liver and kidney function, cholesterol, diabetes risk, B vitamins and more to make sure your body is getting everything it needs to stay healthy.

[1] World Health Organization. (2019). Q&A on the carcinogenicity of the consumption of red meat and processed meat. [online] Available at: [Accessed 20 Feb. 2019].

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