What are carbohydrates? Everything you need to know

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Carbohydrates are an important source of energy, supplying between 40-70% of energy intake in most countries worldwide. You can find them in a broad range of both healthy and unhealthy foods including pasta, rice, bread, biscuits, soft drinks, fruits and vegetables. What impact they have on your health will vary enormously depending on which types you chose.

With this in mind, let’s take a look at how to get the right balance when it comes to your carbohydrate intake.

What are carbohydrates and what do they do?

So, let’s get back to basics. What exactly is a carbohydrate? To put it simply, carbohydrates are one of the three main macronutrients (Carbohydrates, Fat and Protein) that we need to provide energy and nutrients for the body. Carbohydrates are primarily used as a fuel source and are broken down by our digestive systems into glucose.  This provides us with the energy our brains and bodies need to function and are the preferred source of energy.

There are three main types of carbohydrates: starch, fibre and sugars. Different types of foods will contain different amounts and will therefore impact our bodies in very different ways. Let’s look at these three in more detail:

What are starches?

Starchy foods are complex carbohydrates. Complex carbohydrates provide more sustained energy as they take longer for your body to digest. Starchy foods are not only a good source of energy but they provide us with vitamins, minerals and fibre. Examples of starchy foods include beans, bread, cereal products, lentils, pasta, peas, rice, grains, starchy fruit (apples, berries, melon) and starchy vegetables (such as beetroot, parsnips, potatoes, squash, sweet potato and sweetcorn). Wholegrain varieties of starchy foods (e.g. brown bread) are also good sources of fibre.

What is fibre?

Fibre is a complex carbohydrate found in plant foods such as fruits, vegetables, grains and legumes. Broadly speaking there are two types of dietary fibre: soluble and insoluble. Soluble fibre forms a gel like substance in the gut which can help lower cholesterol. Insoluble fibre mostly passes through the digestive system undigested but has a beneficial effect on stool movements and bowel health. Most foods contain both soluble and insoluble fibre.

Examples of fibre rich foods include whole grains (such as wheat, barley, oats, rye, rice, amaranth, quinoa and buckwheat), legumes (such as beans, chickpeas, lentils and peas), fruits (such as pears, raspberries and kiwi fruits), vegetables (such as artichokes, beans, cabbage, carrots, broccoli, fennel, kale, peas and sweet potatoes), seeds (such as chia and flaxseeds) and nuts.

When grains are refined, the refining process removes the outer husk which contains most of the fibre. There are higher concentrations of nutrients and chemicals from plants (also known as phytochemicals) in the outer part of the grain so eating refined carbohydrates will also result in reduced nutrient intake.

Switching from refined bread, flour, pasta and rice to whole grain versions is a simple way to boost your fibre content. If in doubt as to whether it has been refined the clue is usually in the colour. White usually equals refined. Unrefined products tender to be browner.

Most of us don’t eat enough fibre, despite the fact it can help with maintaining healthy bowel movements. Research shows that within the Western world, most of us should increase our dietary fibre intake by around 50% from our current levels with the NHS advising that we aim for over 30g of dietary fibre daily. A healthy gut microbiome also needs dietary fibre to thrive. You can find out about how much fibre you’re getting from food labels, but a daily menu for intake of 30g might include a breakfast of porridge plus fruit and nuts; a fruit snack; lunch including raw veg and hummus; dinner of meat with 3 crunchy cooked veg.

What is sugar?

Sugars are a type of simple carbohydrate. Simple carbohydrates are foods that break down quickly leading to a sharp rise in blood sugar levels. They can be found naturally - such as in honey, fruits and milk - but they can also be found in refined sugars and processed foods, such as sweets, cakes, biscuits, pastries and soft drinks. Not only are these types of refined and processed foods bad for your blood sugar but they also have little to recommend them in terms of fibre, vitamins and mineral content.

Most people are aware that foods like sweets, fizzy drinks, biscuits and ice cream are high in added sugar but many are unaware that processed foods like ready meals, pasta sauces, salad dressings and even yoghurt can be high in added sugar. Always check food labels carefully and remember that the NHS advise that adults should have no more than 30g of added sugars daily. That’s about six teaspoons. For children the level is lower.

For a more healthy and balanced diet, the majority of your carbohydrate intake should come from complex carbohydrates rather than simple.

What is the recommended daily amount (RDA) of carbohydrates?

According to the NHS, adults should be consuming at least 260 grams of carbohydrates a day. The Scientific Advisory Committee on Nutrition recommends that approximately 50% of our food intake should come from carbohydrates.

However, as we have discussed, carbohydrates are not all equal in terms of their health impact. It is interesting to note that the Japanese residents of Okinawa have some of the highest numbers of centenarians anywhere in the world and obtain over 85% of their calorific intake from carbohydrates. Their carbohydrate intake is largely comprised of orange-yellow root vegetables such as sweet potatoes and a wide range of green leafy vegetables. These are nutrient dense, rich in beneficial plant chemicals and quite unlike many of the processed carbohydrates that we would see in a typical Western diet. So try to ensure that your carbohydrates are coming from a wide range of healthy foods rich in vitamins, mineral, phytonutrients and fibre.

The breakdown of carbohydrates

There are many factors that affect how efficiently your body breaks down carbohydrates. If you have a slow metabolism, this could mean that you put on weight more easily.

Understanding your genetic predisposition to metabolise carbohydrates may help you make food choices that work better for you.

Evergreen Life can help you understand your carbohydrate metabolism through home genetic testing kits. The DNA test results provide insights and recommendations into key areas of your health and wellbeing like diet and metabolism, helping you to make more informed decisions about the food you eat.

What are the benefits of carbohydrates?

  • Providing energy - First and foremost, carbohydrates provide us with energy, as we’ve covered earlier in this piece.
  • Providing fibre - Dietary fibre intake has been associated with many health benefits including a healthy gut microbiome, favourable body weight, overall metabolic health, colonic health and lower risk of cardiovascular disease and bowel cancer. There is some evidence to suggest that people who eat higher levels of dietary fibre and whole grains have lower rates of non-communicable diseases compared with people who eat a lesser amount. A study by The Lancet suggested a 15 - 30% decrease in all-cause and cardiovascular related mortality when comparing people who eat the highest amount of fibre to those who eat the least. The study also found that eating fibre-rich foods reduced incidence of coronary heart disease, stroke, type 2 diabetes and colorectal cancer by 16-24%.
  • Providing phytochemicals. Plant based foods such as fruits, vegetables and grains are our main source of dietary phytochemicals. Phytochemical intake is linked with protection from many chronic diseases. Research is ongoing.

Are you eating the right way?

Whilst all this can seem overwhelming, if you focus on getting the majority of your carbohydrates from a diverse range of unprocessed whole grains, beans, lentils and colourful vegetables and fruits then you will be on the right track. All of these come with a whole host of other health benefits including vitamins, minerals, fibre and beneficial plant chemicals.

So what score would you give your food and nutrition? Could you improve it? Our app helps you to discover your Wellness Score and puts you in charge of becoming your own wellness expert with helpful articles like this one on What's in a healthy diet.

Be as well as you can be? Download the Evergreen Life app today and get started on your wellness journey.

Written by
Ingrid Kitzing

Meet Ingrid Kitzing, nutrition expert here at Evergreen Life. She is passionate about helping people bring healthy and nutritious food into their lives.

Article updated:
June 14, 2021
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