Only fruit and veg?

We've talked about the virtues of fruit and veg in just about every blog post, but could you get by if you ate just these and no other foods? It's not something I would encourage anyone to do, but it's an interesting thought.

Fruit and veg fit into a balanced diet, which is one containing a variety of different foods, providing all the nutrients that the body needs. Whilst fruit and veg might be a bigger focus in the diet of a vegetarian or vegan, they would also include foods from the three other main groups - starchy foods (the likes of cereals, rice and pasta), protein rich foods (eggs for some vegetarians, along with pulses, nuts and alternatives such as soya products and Quorn) and dairy foods or their alternatives (think soya, rice and oat milk, ideally fortified with calcium and vitamins).

If you were to include starchy vegetables such as potato, and pulses, which are technically sometimes excluded from the fruit and veg group, as their nutritional composition is generally more similar to foods in the other groups, it might be possible to get away with a diet limited to fruit and veg. However, to ensure you were receiving an adequate intake of all the necessary nutrients, a lot of forward planning would be needed.

Whilst intake of fibre, vitamin C, K, beta-carotene and various B vitamins could easily be achieved when just eating fruit and veg, the following nutrients pose more of a problem, so care would need to be taken:

• Calcium. Admittedly pulses, green veg and dried fruit are a source of calcium, but to meet the target of 700mg for an adult you would need to include these in one day: a 200g tin of baked beans, 120g spinach, 80g each of broccoli and okra - perhaps you could make a curry out of all of these - and 4 figs.
• Iron. Whilst men and women over 50 years of age might be able to achieve the recommended 8.7mg daily from an intake of pulses, green veg and dried fruit, younger women will struggle to achieve their target of 14.8mg daily. For reference 8.7mg iron could be achieved with a cup of prune juice, 200g cooked lentils, a baked potato and a tomato - certainly the latter three lend themselves to the base of a meal very nicely. With plant based sources of iron it is essential to always include them with a source of vitamin C, so this is where green veg, citrus fruits, berries, kiwis and the like come in handy.
• Protein. The majority of us eat more protein than we need - as a general rule adult females only need 45g and males 55g daily - so eating less than we currently do would be no bad thing. The important thing to do though is to ensure that we can obtain all the amino acids - the building blocks that make up protein. Certain amino acids are known as "essential" as they must be obtained from the diet, as the body is unable to generate them from reactions within the body and apart from soya, no other vegetable sources of protein provide all the essential amino acids. Including soya every day would be ideal, but if not possible, including a range of other pulses would help increase your chance of securing all the essential amino acids from your diet, as different plant-based foods have various combinations of the amino acids. To put things in perspective 200g cooked soya beans would provide 32g protein, which you would need to spread over two meals, as pulses are very filling due to their fibre content. All veg has a certain protein content, but without the inclusion of pulses, you would find it very difficult to meet your protein requirements.
• Vitamin D. Unfortunately there are no fruit or veg rich in vitamin D, so you would need to be sure to roll your sleeves up every day to catch some rays from April to September to generate your own by the action of sunlight on your skin.
• Vitamin E. If you were including vegetable oils, vitamin E isn't a problem. If not, you would need to include avocados, sweet potato, broccoli or asparagus daily.
• Essential fatty acids. As with vitamin E, oil is a very good source. Choose rapeseed oil, as not only is this packed with monounsaturated fat - the best type of fat to maintain healthy cholesterol levels - it is also a source of omega-3 fatty acids, which are thought to have a role in the health of the heart, joints and nervous system. Your best bet for vegetable based essential fatty acids - those that the body can't generate - are avocados. Green leafy veg also provide small amounts of omega-3 fatty acids. Throw in some nuts and seeds and your requirements for essential fatty acids and Vitamin E would be easily be met.

So although fruit and veg do contain a range of nutrients, it is hard - though admittedly not impossible - to obtain all that your body requires to remain in good health. The key is to include foods from all the groups - starchy foods, those rich in protein and dairy, or their alternatives, in addition to fruit and veg - in your meals each day.

Photo by Emeraldhorticulture via Wikimedia Commons