When I think about the fundamentals of nutrition, my first thought is usually, and probably the same for you, what makes the diet up. The balance of energy, and the breakdown of how many macro- and micronutrients one gets. At the base level, this is what constitutes nutrition, but I then realise that what we really mean is what are the fundamentals of good nutrition, which is a lot more complex.
The components of the diet are not the be all and end all of nutrition but they are a good place to start. Most people are aware of calories (kcal), carbohydrates, protein, fats (the latter three make up the ‘Macronutrients’), and micronutrients, and have a general idea of what they do. If not, here is a brief breakdown:
Calories – A calorie is a unit of measurement of energy. There is a different number of calories per gram in each macronutrient (included below). The general rule is that if one consumes more calories than are expended, the result is an increase in body mass, if calorie intake is less than expended, body mass will decrease. This is called the energy balance . Of course, it is in no way this simple.
Carbohydrate (3.75kcal/g (this is rounded up to 4kcal/gram on food packaging) ) – their primary use is energy. There are multiple kinds of carbohydrate that take varying lengths of time to digest, if at all.
Protein (4kcal/g) – used for growth and repair. Protein can be found in plant and animal sources, and is used for structures in the body, such as muscle and skin, as well as more functional roles like those in the blood.
Fats (9kcal/g) – another source of energy, fats are also vital in the function of our hormones and communication between our cells. Different types of fat have different properties; this is often dependent on whether it is saturated, monounsaturated, or polyunsaturated.
Micronutrients – consists of vitamins and minerals, they are essential for maintaining good health, though they don’t have an effect on energy balance.
Following this information, we can start to think about what the real fundamentals of nutrition are. A diet is not simply the sum of its parts; we have to think about –
- When we’re eating
- Where our food comes from
- How often we eat
- How do we feel that day
- How active we’re being.
The main purpose of nutrition, we shouldn’t forget, is to nourish – to ensure that we have adequate amounts of the above components to survive and thrive in our environment. The quantities of these nutrients can vary massively depending on body composition, lifestyle or fitness goals, activity level, and much more, but there are set standards such as those from COMA, 1991  to use as a reference. You should find out the quantities that apply to you but be willing to deviate according to the factors stated above. There are also recommendations set out that seek to cover general principles of day to day healthy eating, such as the 8 tips for healthy eating from the NHS , that prescribes eating 5 portions of fruit and vegetables each day, eating a balanced and varied diet, reducing sugar, and several others.
The primary concerns should be the quality of the food we consume, and if you’ve set yourself a goal that needs to be attained through the alteration of your diet the real fundamentals will be CONSISTENCY, ACCOUNTABILITY, and DISCIPLINE. These tools will carry over to far more progress than any calorie equation you can find. It is unfortunately easy to eat in excess, or rely on quick, low quality food, but the smallest amount of knowledge and focus can go a long way toward living a healthier life from your diet. The key is to be flexible enough to adapt to change but strict enough to keep to your dietary principles, which should bear some resemblance to the following (as well as a consideration for the government recommendations mentioned before) –
1. Eat real food – don’t rely too heavily on supplements, and don’t fall into the trap of meal replacement diets. Nutrients found in whole foods are often synergistic with each other meaning that you absorb much more of it in that form.
2. Don’t overeat – the amount you eat will drastically fluctuate depending on what your goals but stuffing yourself until you’re full isn’t healthy method for anyone. Be conscious of how hungry you are and take your time.
3. Drink water – water is involved in every process in the body to some degree. Drink it. Lots of it (6-8 glasses/day is an attainable goal for most)
4. Don’t be so hard on yourself – a healthy diet is, unfortunately, not a typical one – otherwise obesity wouldn’t be as prevalent issue as it is – and therefore we often find ourselves in situations that run contrary to our set eating habits. If you happen to slip and indulge, know that you can just pick it up where you left off and that all your progress won’t be instantly erased. Just make sure that overall you stay consistent and accountable.
 NHS Website (2016) Understanding Calories https://www.nhs.uk/live-well/healthy-weight/understanding-calories/
 British Nutrition Foundation Website Carbohydrate https://www.nutrition.org.uk/nutritionscience/nutrients-food-and-ingredients/carbohydrate.html?start=2
 Committee on Medical Aspects of Food Policy (COMA) (1991) Dietary Reference Values (DRVs) for Food Energy and Nutrients for the UK. Report on Health and Social Subjects 41. London: The Stationary Office
 NHS Website Eat Well; Eight Tips For Healthy Eating (2016) https://www.nhs.uk/live-well/eat-well/eight-tips-for-healthy-eating/  NHS Website Six to eight glasses of water ‘still best’ (2011) https://www.nhs.uk/news/food-and-diet/six-to-eight-glasses-of-water-still-best