What's in a healthy diet?

Eating well is one of the best things we can do to keep ourselves healthy. Our diet and whether it has all the essentials, not only impacts our health but also our energy levels and capacity to enjoy life. It’s sobering to note that people who are obese appear to do worse with COVID-19.

In this article, we'll help you understand the Nutrition Check so you can decide where you need to focus in order to improve your score. Whilst there are many differing opinions about what a healthy diet looks like, we offer some practical tips in areas where experts broadly agree, with links to a lot more information if you want to explore further.

What does a healthy diet look like?

Food is one of the great joys of life, but as well as the taste we need to remember why we must eat. It's for the nutrients, vitamins, minerals and trace elements that our bodies need to function. Briefly that's;

Macronutrients: The three macronutrients are protein, carbohydrate and fat. Carbohydrates and fat are used to provide energy, measured in calories, where proteins are normally used for building structure. ‘Macro’ means large, so these nutrients are required in large amounts. You can learn more about macronutrients here.

Micronutrients; 13 essential vitamins and about 15 essential minerals such as calcium, magnesium, zinc, potassium, chromium, selenium, iodine, iron.

Fibre: Food that is difficult for your body to digest, improves bowel health. It’s found abundantly in fruit, raw and briefly cooked veg, and wholemeal bread.

So where do you find these key nutrients? Well the short answer is in food that is minimally processed or unaltered from its natural state. Our food goals, outlined below, will help you understand a bit more about key elements that should be in a healthy diet.

These tips are not intended for people following specific diets based on medical advice, religious teachings or personal preference. They are also not intended for those with particular needs such as pregnant women.

1. Eat your Greens

Low fruit and vegetable consumption has been linked to poor health. Including them as part of your daily diet may reduce the risk of certain diseases including heart disease and certain types of cancer. Put simply, they are 'nature's pharmacy', including vitamins, minerals, dietary fibre, and a whole host of non-nutrient goodness and antioxidants. 

Current advice, which is 25 years old, is that everyone should have at least 5 portions (80g) a day as a minimum. It's possible that 10 portions per day (800g) could be even better.

2. Meat and proteins

Good sources of protein include eggs, poultry and quinoa, tofu and dairy. Red meat such as beef, lamb and pork is a good source of complete protein, vitamins and minerals such vitamin B12, niacin, vitamin B6, iron, zinc and phosphorus. However, it’s possible that eating too much red and processed meat could increase your risk of bowel cancer.

While processed meat - things like sausages, salami, bacon and ham - are sources of protein, they can contain hidden additives like salt and other potentially harmful chemicals such as nitrites used in curing. The NHS advises if you are eating more than 90g (about the size of a pack of cards) you should cut back to 70g.

Protein is an important part of the diet but try to think of it as a side and the vegetables as the main.

3. Fish and Seafood

A healthy diet should contain at least two portions of fish a week including at least one portion of oily fish. Oily fish, like trout, salmon, sardines and tuna, are rich in omega-3 fatty acids and may help prevent heart disease. Fish is also a source of essential protein, B vitamins and fat soluble vitamins A,D,E.

Omega-3 fatty acids are needed for the correct functioning of our cell membranes. They are important for brain, eye, and heart health, especially during pregnancy and infancy. Fish and seafood such as prawns, mussels, scallops, squid, are good sources of selenium, zinc, iodine and copper. Iodine for example is essential for thyroid hormones.

The source of fish we buy matters. Because of polluted oceans, rivers and seas, many fish contain elevated levels of toxic compounds. Pregnant women need to take special care, such as limiting tuna (it can contain mercury) and avoiding swordfish and raw shellfish. You can get more information in links below.

4. Nuts and seeds

Unsalted, unroasted nuts and seeds are packed full of nutrients like vitamins, minerals, protein, fibre and essential fats.  Diets containing nuts, particularly walnuts which have a unique α-linolenic acid content, have consistently shown health benefits, particularly against heart disease.

Most of the antioxidants are found in the outer skin of the nut, and if you roast or bleach them you’ll lose that, so go for nuts in their natural state.  But go easy, more isn't always better. Nuts contain compound like phytates and lectins which can present problems for some, such as indigestion. A portion is a handful (about 30g).

5. Whole Grains

Whole grains are rich in dietary fibre and micro-nutrients. People whose diets contain whole grains appear to have a lower risk of cardiovascular disease and cancer. That’s food like wholegrain bread, brown rice, oatmeal.

However, while wholegrain is undoubtedly better than the white equivalents, if you want to lose weight, it's worth thinking about how the carbohydrates in all grains can affect blood sugar. More on this in the next tip.

6.  Avoid Sugar

We’re advised to limit free sugars. This is sugar that's found in cakes, sweets, biscuits, chocolate, soft drinks, breakfast cereal and yoghurts etc. You might add sugar yourself to drinks and cereals. But free sugars are also found naturally in honey, unsweetened fruit juice, vegetable juices and smoothies.

Adults should have no more than 30g of free sugars/day, (roughly equivalent to 7.5 x 4g teaspoons). These are examples of free sugar content.

Table 1: Free sugar

Free sugar quantities
Free sugar examples

Table 2: How each food affects blood glucose compared with one 4g teaspoon of sugar

It’s worth knowing that certain foods are rapidly converted to sugar when we eat them. That's many carbohydrate containing foods such as bread, rice, pasta, potatoes, cereal, fruit juice. The table below, based on data from Dr David Unwin and phcuk.org, shows the equivalent amount of blood glucose in various foods. If you want to lose weight, try to be aware of these hidden sugars.

Food for thought:

Fats: Current UK government guidelines advise cutting down on all fats and replacing saturated fat with some unsaturated fat. The rationale for this is too much fat in your diet, especially saturated fats, can raise your cholesterol, which increases the risk of heart disease and calorie intake. The fat contained naturally in many foods is a mixture of saturated and unsaturated fat. As a general rule, saturated fat is solid at room temperature while unsaturated is generally liquid.  Trans fats, are found in fried, processed and baked foods and these have little nutritional value and are most harmful to health.  They are sometimes labelled “partially hydrogenated vegetable oil” and you can find out more about them here.

The guidance on fat intake is currently under debate as an increasing number of experts are now arguing that there is little evidence natural fats are the cause of obesity and poor health.

Salt: Too much salt can lead to high blood pressure which puts a strain on our heart and blood vessels and that’s why official guidance is that salt intake should be limited to 6g a day, that's around 1 teaspoon. It's important not to add too much salt to your food but also to be aware of foods which have high salt content, such as processed meats, salted nuts , cheese and stocks.

However, some doctors have noticed that when people adopt low carbohydrate diets, they urinate more frequently, lose sodium and their blood pressure falls. It’s an interesting observation which again points to excess sugar being implicated. There’s more information in the links below.

Extra Boosts : There are some additional extras that could be helpful. Adding herbs and spices offers flavour plus essential vitamins, minerals and antioxidants. Don’t forget though, salt is not a spice.

Your Microbiome: Trillions of microorganisms live in our intestinal tract and help us digest food and absorb nutrients. This is our gut microbiome and its unique to each one of us,  so even the best dietary advice might not be right for you personally. It's predicted that microbiome testing could become an important strand of personalising nutrition and even managing health conditions in the future.

The bottom line

There’s no ONE diet that’s perfect for everyone. The exact makeup of a healthy diet will vary based on your age, gender, genetics and degree of physical activity. But sticking to a few good rules should help.

Check out our diet insights

Remember, small changes over time add up to big results in the long run, so if you’re new to improving your diet, perhaps change one or two things and see how you feel. Retake the nutrition check once you’ve made the changes to see how your Wellness Score in your app is affected.

A DNA test will help you gain a greater understanding of how your body processes a number of foods and whether you are prone to vitamin deficiencies You can order a DNA test kit here

And if you want to dig deeper, there are loads of helpful links in the references below to explore further.

References