The ultimate guide to nutrients and food

You hear about them all the time. Come January, everyone seems to be monitoring their calorie intake and casting a watchful eye over their step count.

But what is a calorie? First and foremost, calories are units of energy. Calories refer to the amount of energy food sources we put into our body, as well as the amount of energy we expend on a daily basis.

The majority of our calorie intake is used to keep us ticking over: think blood circulation and brain functionality. The rest is either used when we exercise or if we’re somewhat overindulgent, stored as fat to keep us warm on those cold, winter nights.

The NHS recommends a daily intake of 2,500kcal (male) and 2,000kcal (female) in order to maintain healthy body weight – but this will, of course, depend on how much physical activity you’re doing. If you’re smashing out HIIT session after HIIT session, you’re going to need more energy than, say, a couch potato and thus your calorie intake will need to be higher.

And whilst calorie intake is important – we need to be putting in the same amount of energy as we’re using up – not all calorie sources are the same: for example, the benefits from a can of coca cola will vary significantly from those of a bowl of pasta.

Everyone in the fitness industry is tracking them. Myfitnesspal has become sport’s best friend. But what exactly are macronutrients? And why is everyone obsessing over them?

Macronutrients (macros) are the compounds we need to eat in order to provide us with calories/energy. We require them in fairly large amounts (even larger if you’re an 18st rugby player) and each have their own specific role to play. 

You will already know what macronutrients are, as this is just the collective term for them. They are protein, carbohydrates and fats.

Protein forms the building blocks for cells in the body and is essential for muscle repair and building. You’ll hear bodybuilders around the gym screaming for protein, and that’s because intense physical activity involves breaking down muscle tissue. Protein aids in protein synthesis. In other words, it assists your body in creating new muscle tissue to replace and add to the damaged ones.

Examples of foods high in protein 

• almond milk • unsalted almonds • beef mince (5% fat) • beef steak • chicken breast (no skin) • eggs • greek yoghurt (0%, low-fat and full-fat) • lamb • milk • unsalted peanuts • salmon • tofu • tuna • turkey breast (no skin)

Runners, cyclists, triathletes, skiers, boarders and anyone doing any form of long-enduring physical activity rely on them. They are our main sources of energy.

You might have heard it said that carbohydrates (carbs) are bad for you – after all, where did the adage ‘no carbs before marbs’ come from? But that’s not strictly true. Whilst there are forms of ‘bad carbs’, there are plenty of good, essential ones that we need in order to survive and live a long and healthy life. Carbs can be broken down into sugar, starch and fibre. 

Sugars: the bad carbs people speak of are simple carbs, such as those found in fizzy drinks, chocolate, breakfast cereals and flavoured yoghurts. Their simple structure means they are broken down by the body almost instantly and then turned into fat. Not good. 

Naturally occurring sugars, however, like those found in milk, fruit and vegetables do not fall into this same, ‘bad for you’, category.

Starch: think pasta, potatoes, bread and rice.
 
Fibre: think vegetables, wholewheat pasta and lentils.

Unlike simple sugars, starch and fibre are known as complex carbohydrates: they take longer for the body to process and prove vital to things like gut health, reducing the likelihood of diabetes and reducing cholesterol levels.

So should you have a low carb diet? We’d say stay low on the bad sugars; remain high on starch and fibre.

Examples of complex, starchy carbs  

• beetroot • wholemeal bread • brown rice • carrots • green beans • legumes (beans, chickpeas, lentils) • oats • pasta • potatoes (white and sweet) • rice cakes • wholemeal tortilla wraps • quinoa

Examples of non-starchy carbs  

• asparagus • berries • broccoli • Brussel sprouts • cabbage • cauliflower • kale • mushrooms • onions • peppers • spinach • tomatoes

They’ve got a bad reputation, but they’re absolutely vital, the human body cannot function without them. There’s a good and bad version of everything, and fats are no different.

What are the different types of fat?

Essential fatty acids (EFAs): these help lower blood cholesterol and reduce inflammation. Think omega-3 and omega-6. These are found in things like oily fish (mackerel and salmon), corn, soya and walnut oils.

Monounsaturated fats: found in foods like olive oil, nuts, seeds and avocados – these are considered healthy as they reduce the level of harmful cholesterol in the blood.

EFAs and monounsaturated fats fit into the category of unsaturated fats.

Saturated fats: these are found in most animal products (meat, butter cheese etc.) and have garnered a bad rep in recent years. Whilst high quantities can increase levels of cholesterol, they also provide a vital role in hormone production.

Trans fats: if saturated fats aren’t good for you, trans fats definitely aren’t. Found in processed foods, cakes, biscuits and some ready-made meals, they raise cholesterol quite considerably.

All in all, while the world of fats may seem rather convoluted, by focussing on swapping saturated fats to unsaturated fats (EFAs and monounsaturated), you’re already way ahead of the crowd.

Examples of healthy fats  

• almond butter • avocado • chia seeds • dark chocolate • herring • mackerel • olive oil • peanut butter • salmon • sardines • trout • full fat yogurt