Like most things in life, balance is the key. Work vs personal life, activity vs rest, being asleep vs being awake – all need to be balanced out so that one thing doesn’t overwhelm the other. Where the level rests will differ from person to person, but striking the correct individual balance is necessary for both physical and mental health. Your diet is no different.
Getting back to basics, humans need food for two main reasons:
- To supply the body with nutrients – allowing our body to build, grow, repair and reproduce
- To supply the body with energy – fuelling all of our functioning and bodily processes
Other than breastmilk as a food source for babies, no other food contains all the essential nutrients our body needs. For this reason, a diet must be varied to obtain all the nutrients we need to survive and thrive.
The exact make-up of a diversified, healthy diet can, and will, vary depending on individual characteristics – age, lifestyle, cultural setting, dietary quirks and local food availability. However, the principles and nutritional elements that underpin a good, balanced diet remain true.
A human body cannot produce everything it needs to function; this is where eating comes in. There are seven main classes of nutrients a person has to consume through their diet for the body to maintain health, grow, recover and repair.
These are: carbohydrates, proteins, fats, fibre, vitamins, minerals and water. These seven essential nutrients can be sub-divided into two top-level categories:
- Macronutrients – needed in larger amounts
- Micronutrients – needed in smaller amounts
Carbohydrates, proteins and fats make up the macronutrients, often referred to just as macros, which do a lot of the heavy lifting for the body. Macros are needed for a whole variety of purposes: energy supply, growth and everyday metabolism – breathing, pumping blood around the body, building new cells and many other processes you probably don’t think of as requiring energy.
As such, they constitute a much larger portion of a balanced diet when compared to micronutrients. Let’s take a quick look at each.
These are the body’s primary energy source and come in many shapes, sizes and forms.
Carbohydrates are important for the proper functioning of the brain, kidneys, central nervous system and muscles. If carbs aren’t used straight away after they’re broken down, they usually get stored in the skeletal muscles and the liver in the form of glycogen.
All carbohydrates are built from blocks of biomolecular sugar, such as glucose or fructose. The type of carbohydrate depends on how many sugar molecules are bound together. One or two molecules of sugar (called monosaccharides and disaccharides) are more easily known as simple carbohydrates. These provide the body with a rapid form of energy. Simple carbohydrates are found in sugary drinks, sweets, cookies and concentrated fruit juice.
When more sugar molecules are chained together you get polysaccharides, which are complex carbohydrates. These can be more easily identified as starchy carbs, such as potatoes, oats, rice, wholegrain foods. Complex carbs tend to pack in more vitamins and minerals than simple forms and digest more slowly in the body.
Complex carbohydrates also contain another important nutrient alongside starch – dietary fibre. Although we cannot digest fibre and it doesn’t provide us with any energy, it’s essential to our digestive health. Fibre helps feed the friendly bacteria in our digestive system, helps promotes bowel regularity and lowers the risk of disease, such as diabetes and heart diseases. More fibrous carbohydrates include fruits, vegetables, nuts, beans and wholegrains.
For many, protein has become almost synonymous with muscle. This seriously does this incredibly important macronutrient a disservice.
After water, protein is the most abundant nutrient in the body, and it’s the primary component of not just muscles, but organs, skin and hair. Protein provides the building blocks for the production, maintenance and repair of cells and tissues in the body, whilst also helping to fight infection, make hormones and enzymes, regulate body functions and plenty more still. When carbohydrates and fats aren’t available, protein can also supply the body with energy.
The important building blocks that make up all proteins are called amino acids. There are around 21 amino acids in the body – of which 12 can be produced internally, but 9 are considered ‘essential’ and need to be taken in through our diet.
Excess protein can’t be stored in the body, so we need to take this macronutrient in daily. Food groups with high levels of protein include meat, seafood, eggs, poultry, beans, nuts and dairy products.
Often just considered an unwanted layer of tissue under our skin, fats are perhaps the most misunderstood macronutrient out there. Fat is an essential nutrient that plays many roles – it acts the body’s primary source of energy storage, insulates our bodies and protects our organs, initiates chemical reactions and plays a part in other basic metabolic functions, such as new cell growth, muscle movement, cell signalling, brain functioning and vitamin and mineral absorption.
Fats can be broadly classified into two mains groups: saturated and unsaturated.
Most saturated of these come from animal sources, such as meat and dairy products, but can be eaten via plants as well, for example, palm oil and coconut oil. Eating too many saturated fats can have negative health implications via increasing body weight and cardiovascular disease.
Unsaturated fats have well-established health benefits with the heart, LDL cholesterol levels and links with reducing rheumatoid arthritis. Sources include vegetable oils, olive oil, avocado, nuts, seeds, peanut butter and fatty fish.
Made up of vitamins and minerals, micronutrients are essential for almost all bodily functions and cell processes, despite only being required in very small doses (milligrams and smaller).
The sphere of influence and range of health benefits from vitamins venture from boosting the immune system and preventing certain diseases, to supporting healthy blood and aiding the brain and central nervous system. Micronutrients also play an important role in energy production and the removal of free radicals from cells. There are currently 13 recognised vitamins.
Minerals, such as magnesium, calcium, potassium, iron and zinc, also play key roles within the body. They help to balance water levels, maintain healthy skin, hair and bones, help carry oxygen in the blood and support the immune system. They are also integral to enzyme functioning.
Deficiencies in certain micronutrients can cause illness, developmental problems and other issues from anything to do with vision, dental health and bone development, to ability to heal wounds, keep the skin healthy and maintain healthy blood.
Special Mention for Water
Often taken a little for granted, water is the ultimate unsung hero. It’s an essential nutrient and the key substance for life as we know it. Consumed in macronutrient quantities, almost all metabolic processes and chemical reactions in our body, from breaking down glucose in our cells to absorbing oxygen through our lungs, depend on water. An average adult needs around two to three litres of water every day.