Many people believe that the crux of a healthy diet is the exclusion of unhealthy foods. However, rather than just focusing on cutting things out, a good diet should also incorporate an increased intake of nutritious, health-boosting foods.

Fortunately, there are many foods out there which will improve health and wellbeing as well as protect against future illness. Here are 10 of the best.

1. Nuts

Although nuts are high in calories and so should be eaten in moderation, the calories in nuts come mainly from their high levels of monounsaturated fats, which are extremely good for health. Eating foods rich in these fats can help reduce bad cholesterol and lower your risk of heart disease and stroke. As well as their heart benefits, nuts are also a great source of protein and are packed with fibre, antioxidants, fatty acids and vitamins and minerals. It is worth noting that peanuts are actually legumes and have different nutritional properties from tree nuts, but there are many other good options to pick from including Brazil nuts, cashews, walnuts, pecans and pistachios.

2.Oily fish

Oily fish - such as salmon, mackerel, sardines and trout - are renowned for their health benefits when eaten in moderation (between two and four portions a week). Not only are they a great source of vitamins and minerals - including immune-boosting vitamins A and D - but they are rich in omega-3 fatty acids. These super healthy unsaturated fatty acids have many health benefits, having been linked to a lowered risk of heart disease, brain damage, stroke, dementia and prostate cancer. Research findings published in the British Journal of Ophthalmology also suggest that omega-3 fatty acids can benefit eye health by halting the progress of age-related macular degeneration.

3. Beetroot

Beetroot is one of the latest vegetables to be hailed as a 'superfood', and looking at its reported health benefits it is easy to see why. Various studies have suggested that drinking beetroot juice can improve stamina when exercising, lower cholesterol and blood pressure, improve heart health and liver function, reduce risk of dementia, and fight against cancer. The versatile vegetable is also a good source of many vitamins and minerals, including vitamin C, which is important for tissue growth and repair, and folate, which helps to reduce the risk of birth defects in unborn babies, as well as helping to prevent anaemia.

4. Onions

The onion family (part of the genus Allium) contains many foods that may do wonders for our health including onion, garlic, leeks and chives. Studies have suggested that both onions and garlic can help lower cholesterol, while findings published in the Journal of Nutrition showed that onions could help lower blood pressure. Onions and garlic also have antiviral and antibacterial properties, so can help to fight against bacteria and illness in the body, while a study by researchers at the King's College London and the University of East Anglia found that eating foods from the onion family could help prevent hip osteoarthritis.

5. Dark, leafy greens

Dark, leafy greens such as spinach, watercress and kale are automatically associated with healthy eating for many due to the "eat your greens mantra" that has been drummed into our heads over the years. However, this faith in the health properties of green veg is well-founded, as these vegetables are bursting with nutrients including iron, calcium, potassium and vitamin C, and packed with health-boosting phytonutrients. Some of the reputed health benefits of eating your greens include lowered blood pressure, improved eye health and a reduced risk of cognitive decline.

6. Quinoa

Quinoa has only recently become widely available and well known in many places, but it has quickly become popular with healthy eaters due to its great body benefits. Mostly treated as a grain (although it is actually a seed), quinoa can be used in the place of pasta, wheat or oats for an extremely nutritious meal. Quinoa, like most grains, is high in fibre, making it great for the digestive system, but perhaps its best attribute is that it is one of the few plant sources of high quality protein, containing all eight essential amino acids. On top of this, quinoa is a great source of nutrients including magnesium, manganese, iron, calcium, potassium and several B vitamins.

7. Berries

Acai berry, blueberry, goji berry, blackberry... With a new "super berry" hitting the headlines seemingly every week, it can be hard to keep up with which berry you should be buying this week. Luckily, the truth of the matter is you generally can't go wrong with any commercially available berry. These super healthy fruits are extremely high in antioxidants and have many individual health benefits, including the ability to help prevent dementia (blackcurrants and boysenberries), fight off colon cancer (blueberries), improve vision (bilberries) and ward off urinary tract infections (cranberries).

8. Oats

Grains are notoriously good for our health, but the closer they are to their natural state when eaten the better their benefits, meaning that whole oats are a particularly good choice of grain. Oats not only contain many minerals - including zinc, iron and calcium - but they are a good source of B vitamins, which are great for the nervous system. This popular breakfast ingredient has countless other health benefits; helping to reduce the risk of heart disease and diabetes, lower cholesterol, reduce blood pressure and benefit the digestive system. Oats are also a great source of slow release energy, meaning that they will keep you feeling full and active for longer.

9. Beans

From the macrobiotic to the student, many diets rely on the humble bean in its dry, tinned or baked form - and this could be great news for our health. Studies have found that beans are not only excellent weight-loss and energy foods, but they are a great source of antioxidants, protein and nutrients (such as iron, manganese and B vitamins). Beans are also an excellent source of soluble fibre, which can help to reduce cholesterol, stabilise blood sugar and improve the digestive system, while a study by scientists at the University College of London showed that beans can also help prevent cancer.

10. Tomatoes

With many people turning to expensive "superfoods" to safeguard their health, basic salad ingredients such as the tomato are often overlooked for their health-giving properties. However, a 2008 publication of collated research findings - The Red Bodyguard by Ron Levin and Gerald Cheshire - demonstrated the health properties of this common fruit. Some benefits attributed to eating the tomato included a strengthened immune system, better heart health, the neutralising of free radicals and safeguarding of disease (including cancer) and the prevention of blood clots.