What to Eat When You're Pregnant and Vegetarian : Planning a healthy diet (part 1) - The five food groups - Fruit and vegetables, Starchy foods

1 Fruit and vegetables

Try to eat at least five portions of a variety of fruit and vegetables every day. This can include fresh, frozen, canned and dried products, as well as juices and smoothies. So, your five-a-day could come from a glass of orange juice with breakfast, nuts and raisins mid-morning, salad in a sandwich, and cauliflower and chickpeas in a curry. Fruit juice only counts as one of your five-a-day, no matter how much you have, and the same goes for beans and other pulses. This is because juice contains less fibre than whole fruits, and pulses have fewer micro-nutrients than other vegetables.

Fruit and vegetables don’t have to be expensive. Good old carrots provide plenty of health benefits at a fraction of the cost of foods such as blueberries. However, try to eat as wide a variety of differently coloured fruits and vegetables as possible. That way you are more likely to get a full range of different vitamins, minerals and phytochemicals.

Fruit and vegetables are a valuable source of fibre, which is important for digestion and preventing constipation. Adults should consume about 18g of fibre (technically known as non-starch polysaccharides, or NSP) per day. A piece of fruit, such as one apple or orange or a portion of carrots, supplies about 2g. Some vegetables, such as peas, supply more, about 3.5g per portion.

2 Starchy foods

Foods such as breakfast cereals, bread, rice, couscous, potatoes and pasta provide starchy carbohydrates, also known as complex carbohydrates or good carbohydrates. The other kind of carbohydrates is sugars or ‘simple carbohydrates’, which are found in foods such as white sugar, biscuits and fizzy drinks. Starchy foods should make up about a third of your diet. They are the main source of energy (calories) in our diets and it is good to base each of your meals around one of these foods. It is suggested that about 50% of a person’s calories should come from carbohydrates. They contain fewer calories per gram than fat, making carbohydrate-rich foods better than fatty ones for avoiding excess weight gain. The fact that vegetarians tend to eat more carbohydrates and less fat than non-vegetarians partially explains why they are usually slimmer.

It is generally better to eat unrefined starchy foods rather than refined ones. That means foods like wholemeal bread, brown rice and pasta, and wholegrain breakfast cereals (such as bran flakes and muesli), rather than white bread, white rice and pasta, and cornflakes. Wholegrain products provide extra fibre, as you can see in the table below. There are two different types of fibre: insoluble and soluble fibre. Foods such as bran flakes provide insoluble fibre, generally known as roughage, which helps food move through the digestive system, so you don’t get constipated. Others, such as oats, provide soluble fibre, which helps to stabilise blood sugar levels.

The impact that a carbohydrate-rich food (‘carb’) has on blood sugar or blood glucose levels is known as its glycaemic index, or GI. Low-GI foods such as oats and lentils are broken down slowly, so they keep you feeling fuller for longer. As the carbohydrate is released gradually, they produce only a small fluctuation in blood glucose. High-GI foods, by contrast, result in blood sugar levels increasing more rapidly and to a higher level, and then dropping off more steeply. High-GI foods include refined starchy foods such as white bread and also sugary foods like cakes, biscuits and sugary drinks. Less refined foods tend to have a lower GI. For example, the GI is lower for muesli than for bran flakes, which in turn have a lower GI than cornflakes. Likewise, granary bread has a lower GI than wholemeal bread, which has a lower GI than white bread.

To directly compare one food with another, the glycaemic load (GL) is probably more useful as it takes into account the amount of carbohydrate in a typical portion. This makes it easier to assess a food’s impact on blood glucose levels. If you want to find the GI or GL of particular foods, there is a wide variety of apps and guidebooks available. Consuming low-GI or low-GL foods as part of a healthy (but not low-calorie) diet has several advantages. Women consuming more low-GI foods are less likely to put on too much weight and there is less risk of their baby being very large. Low-GI diets also reduce the risk of having a baby with a neural tube defect, particularly among overweight women.

As well as helping to stabilise blood sugar levels and providing more fibre, unrefined cereals naturally contain higher levels of certain vitamins and minerals. Wholemeal bread, for example, contains 50% more iron and vitamin B₆ than white bread and more than twice as much potassium and zinc. Unfortunately, high-fibre foods also contain phytate, which binds to certain minerals, including calcium, iron and zinc, and reduces the amount that can be absorbed. Therefore having a very high fibre diet, with foods such as brown rice and lentils, at every single meal isn’t necessarily a good thing for maximising mineral absorption. If you eat only unrefined starchy foods, then it might be worth occasionally having white rice or pasta instead. Bran has particularly high phytate levels and is best avoided .