No matter what time of year, eating a healthy, balanced diet – along with regular exercise – is essential for staying in shape and warding off health problems like diabetes, obesity and stroke.

It's all well and good having a strong knowledge of healthy foods, but that's no use if you don't know how to incorporate them into your diet.

You've probably heard the term 'functional food' – but what does it actually mean? A food is described as functional when it is packed full of nutrients, unprocessed and has a physiological effect on health and wellbeing.

It is important, therefore, to introduce functional foods to your diet – if you haven't already. We've picked our favourite functional foods, so why not follow our tips for making them into healthy meals?

Chia seeds

Some people struggle to get the recommended amount of fibre into their diet each day, which can lead to them experiencing problems such as constipation, and in more severe cases, diabetes.

This is where chia seeds can help. Packed with fibre, magnesium and omega-3 fatty acids – all of which aid digestion and heart health – the small seeds provide a powerful boost of nutrition.

You can add chia seeds to your diet in a number of ways. They are great for adding to dishes as a topping, simply by sprinkling them over healthy meals such as porridge, adding them to a chicken or vegetable stir-fry, and even to soups, salads and cereal.

The versatility of chia seeds means that you can benefit from their goodness each day. What's more, their wholesome flavour and crunchy texture is sure to add a kick to what may seem like the dullest of dishes.

Sweet potato

While you might associate potatoes with their fried form found at many fast-food chain outlets, you'll be pleased to discover that the sweet potato is actually more nutritious than its ordinary, non-sweet counterpart.

Sweet potatoes are a good source of vitamins A and C, as well as fibre and carbohydrates. Past studies – including one conducted at the Linus Pauling Institute at Oregon State University – have shown that increasing your consumption of sweet potatoes reduces the risk of diabetes, heart disease and obesity, while promoting increased energy levels and a healthy complexion.

Sweet potatoes have a creamy, sweet and spicy flavour that makes them ideal for adding to savoury dishes. Cut them into wedges and drizzle with a little olive oil, then bake in the oven until crispy on the outside and soft in the middle. Serve with a grilled chicken breast and some green vegetables for a delicious and healthy dinner.

The versatility of the sweet potato means they can also be added to desserts. Make sugar-free sweet potato and chocolate brownies using raw cocoa powder and adding raisins and dates as a natural sweetener.

Goji berries

Goji berries have been used in traditional Chinese medicine for many years and are hailed as a modern day functional food.

They are packed full of antioxidants that work to ward off high blood pressure and diabetes, while their high vitamin A content may protect against skin damage.

Goji berries can be consumed raw or in dried form, similar to raisins. They work well when added to whole grain cereals or homemade healthy desserts, such as fat-free Greek yoghurt with almonds and a drizzle of honey.