Eating a healthy diet when on a gluten-free diet - advice about diet and nutrition

It is natural to feel anxious about the impact your diagnosis has had on your nutritional status, and about the ongoing effects of your new dietary limitations on your well-being. But it is perfectly possible to eat well on a gluten-free diet (GFD) – and you may find you eat more healthily than before.

Eating a healthy diet

So much is written nowadays about eating healthily that you can easily become overwhelmed with the unnecessarily detailed and sometimes contradictory advice given. It’s easy to form the impression that nutrition is complicated. It isn’t. In reality, sticking to a few basic principles should ensure that you maintain good dietary habits.

Possibly the most important principle of the gluten-free diet is variety: try to eat as diverse a diet as possible. You may not want to spend time fretting over which food offers which nutrient, but you can obtain a wide range by mixing it up as much as possible. Avoid coming to rely on any one ‘safe’ food that provides only a limited range of nutrients; overconsumption can also increase your risk of becoming intolerant to a food.

How you eat is vital too. Take your time – when you’re selecting food, preparing it and most importantly eating it. Eat when you’re calm and relaxed and can focus on your meal, not when rushed or distracted, as mistakes are more likely then. Remain quietly vigilant and on guard – always. Take care not to become complacent about eating habits – continue to check labelling and to monitor your diet.

Also, don’t skip meals, especially breakfast – you’ll experience uncomfortable fluctuations in energy and blood sugar levels, and you’ll be more vulnerable to casual snacking and grabbing possibly unsafe convenience foods on the go. Plan ahead, and always have good safe foods to hand in case you should be caught short and feel peckish during the day.

Essential foods

Several food groups are key to your daily diet.

Complex carbohydrates

These include all grains, such as rice, quinoa and millet, and the foods based on them, such as gluten-free (GF) pastas, breads and cereal products. Potatoes also fall into this category. Roughly eight to ten daily servings for teens and adults and approximately four to seven for children are required to ensure an adequate intake of slow energy-releasing carbohydrates and of fibre. A slice of gluten-free bread, an egg-sized potato, three tablespoons of GF muesli and two heaped tablespoons of cooked rice approximate to a serving each.

Protein foods

Two to three servings of meat, fish, eggs, beans, nuts or seeds are advised. A portion is equivalent to 100g of meat or fish, two eggs, three tablespoons of beans or a handful of nuts and seeds.

Fruit and vegetables

Fruit and vegetables are essential sources of carbohydrates, fibre, vitamins, minerals and antioxidant chemicals, and you should aim to consume at least five portions daily, preferably more, and in a variety of colours. A handful of berries, an apple, a banana, three tablespoons of peas or lentils, and two heaped tablespoons of salad are roughly equivalent to one portion.

Dairy foods

Two or three servings of either milk, yoghurt or cheese are recommended by dietitians. A matchbox-sized chunk of hard cheese, a small pot of yoghurt or a glass of milk each provide a serving. Avoid too much cream or butter, as these are high in fat.

Healthy fats

Some fats are needed in the diet, and these may come from some of the foods mentioned above. Unsaturated fats – found in fish (especially oily fish), nuts, seeds, avocados and vegetable oils such as olive oils – are the best.

Water

Two litres daily is the often-quoted figure to which we should supposedly all aspire, but the quantity depends on so many factors – the size of the person, the amount of activity undertaken, the temperature and environment – that it’s misleading to generalize.

A good barometer of healthy and adequate hydration is the colour of your urine: too dark signifies that you may lack fluids, so aim to drink enough to keep your pee straw-coloured. Water itself is the best hydrator, but fruit juices, squashes, sodas and milk all contain mostly water and count towards your quota, as do, within reason, teas, coffees and colas. The dehydrating effects of the caffeine in these drinks are hugely exaggerated by many complementary nutritionists but research shows they are negligible. Alcoholic drinks, which dehydrate heavily, certainly do not count.

The eatwell plate

The eatwell plate is an FSA pie chart representing the proportions of food groups that you should consume in a healthy, balanced diet. It can be viewed at:

The eatwell plate

The eatwell plate principles can be applied to the gluten-free diet, and the approximate percentage shares to aim for are:

• Fruit and vegetables – 33 per cent (i.e. one-third)
• Natural and rendered sources of carbohydrates (potatoes, rice, other GF grains, GF breads and GF pastas) – 33 per cent (one-third)
• Dairy products – 15 per cent (one-seventh)
• Protein-rich foods (i.e. meats, fish, eggs and pulses) – 12 per cent (one-eighth)
• High-fat and high-sugar foods – 7 per cent (one-fifteenth).

Non-essential foods

In moderation, other foods are permitted in the context of a healthy GFD, but take care not to overindulge.

Convenience and snack foods

It’s wise to limit your intake of junk foods, desserts, sweet products and processed snack foods, partly because they are high in saturated fats.

Trans fats are a particular class of fats manufactured during hydrogenation – a process that converts liquid vegetable oils into solid fats and margarines – and they are often used to prolong shelf life. They are unhealthier than saturated fats, offer no contribution to nutrition, and are linked to high cholesterol and cardiovascular disease. Typically, trans fats are found in pastries, cakes, biscuits, convenience meat products such as pies and sausage rolls, and some takeaway foods. Be wary of ‘free-from’ foods listing hydrogenated or partially hydrogenated vegetable oil or fats on the label, as these may contain trans fats. Many manufacturers have a ‘no trans fats’ policy.

You should also take care with the salt content of nibbles such as crisps (which aren’t always free from gluten). Salt can dull the taste buds and contribute to high blood pressure.

Sugary treats

Cakes, biscuits, pastries, chocolate bars, sweets – most of us love occasional treats, and they may be important for your psychological health, especially if you’re feeling down about having to exclude gluten. Eat sugar sparingly, though – no more than 10 per cent of your daily calories should come from sugar, which is roughly equivalent to 50g or 12 level teaspoons. Read labels carefully for added sugars.

Caffeine

Moderate caffeine consumption is safe for most adults, but avoid drinking more than four cups of coffee daily in order to stay within recommended guidelines, and remember that black and green teas, cola, cocoa and chocolate products all contain caffeine.

Alcohol

Moderate alcohol consumption – up to two or three units a day – is generally considered fine for most adults, and although you may be advised to abstain for a while after your diagnosis while your gut heals on the gluten-free diet, there’s no reason why you won’t ultimately be able to enjoy spirits, wine and GF beers. The health risks of excessive alcohol consumption aside, as a coeliac you do need to take extra care as drinking can reduce your vigilance – it’s easy to thoughtlessly pop a pretzel from the bar into your mouth when you’ve had a few more than you should.

‘Free-from’ foods

These have their place, and can be useful, but some products may contain high levels of refined carbohydrates, fats and additives – notably the ‘treat’ foods. The best products are likely to be the staples found on prescription, some of which are fortified with nutrients.

Coeliac nutrition

Getting you off a gluten-containing diet is the priority when you are diagnosed, but establishing yourself on a nutritionally complete diet comes a close second – joint with the need to resolve any nutritional deficiencies stemming from poor food absorption due to your damaged gut lining that may have been caused by a delay in your diagnosis. These may have been picked up during the diagnostic process, but your dietitian may order further blood tests to get a current picture.

Some minerals and vitamins of particular concern are discussed here.

Calcium

This is a vital mineral for healthy teeth and bones and, as a result of poor absorption, you will possibly be deficient in it, and have a need for higher levels in your diet. Your dietitian may also recommend supplements. Long-term low calcium intake can put you at risk of osteoporosis (brittle bones) in later life.

Children with coeliac disease do not have an increased need above the ordinary recommended levels.

Foods rich in calcium are:

• All dairy foods
• Fortified gluten-free flours and breads
• Fortified soya products and tofu
• Fortified vegetable milks
• Leafy green vegetables
• Beans and pulses
• Seeds and nuts
• Bony fish

Iron

This is a vital mineral for healthy blood and, again because of poor absorption, you may well be iron-deficient and have anaemia. This is of particular concern in teenage girls and young women. Your dietitian is likely to recommend supplements to normalize your iron levels, but will also suggest iron-rich foods to incorporate into your diet.

Foods rich in iron include:

• Red meat
• Oily fish
• Egg (especially the yolk)
• Fortified gluten-free breads and cereals
• Amaranth and quinoa
• Dried fruits, such as figs and prunes
• Dark green vegetables
• Lentils and chickpeas
• Soya and tofu
• Nuts and seeds.

The absorption of iron can be reduced by tea and coffee, so avoid these with or soon after meals. Absorption can be helped by vitamin C, so it’s good to drink juice with an iron-rich meal.

Magnesium

Deficiency in this mineral is common, not only in newly diagnosed coeliacs but in the wider population too. Magnesium is essential for the formation and maintenance of bones and tooth enamel, and deficiency can increase the risk of brittle bones.

Foods rich in magnesium include:

• Fish, meat and dairy products
• Amaranth, buckwheat and quinoa
• Green vegetables (e.g. spinach, broccoli)
• Nuts and seeds
• Beans and pulses

Zinc

This is a ‘wonder’ mineral in that it has many functions in the body, and many newly diagnosed coeliacs may have compromised levels. It is essential for the digestion of food, for growth and body tissue repair, for immunity and defence, and for sexual health.

Foods in which zinc is found are:

• Red meat and poultry
• Eggs and dairy products
• Shellfish (e.g. oysters, lobster, crab)
• Nuts, especially Brazil nuts
• Soya and other beans
• Wild rice

B vitamins

The many B vitamins have abundant roles in the body, and there has been concern that coeliac diets are naturally lower in them, because substitute products such as GF cereals do not contain as high levels as regular cereals because they are less likely to be fortified with B vitamins.

Folate (folic acid)

Deficiency of this particular B vitamin, common in coeliac disease (CD), may contribute to anaemia, because it is involved in the production of blood cells.

Foods in which it can be found include:

• All green vegetables
• Corn
• Pulses, chickpeas and beans
• Oranges
• Wild rice and millet

Vitamin B12 

Needed for growth, development and the healthy functioning of the nervous system, vitamin B12 is required in conjunction with folate to produce blood cells, so a deficiency, which is an occasional problem in coeliac disease, can also lead to anaemia.

Vitamin B12 is found in:

• Meats and fish
• Eggs and dairy products

It is not found in naturally vegan foods, so if you don’t eat animal products, alternative sources are:

• Fortified soya foods and vegetable milks
• Fortified yeast extracts
• Fortified margarines

Vitamin D

Deficiency in vitamin D is another common problem in coeliacs. The vitamin is needed, with calcium, to optimize bone health. It is made in the body by the action of sunlight on the skin, and so a little light exposure daily is important.

Good food sources include:

• Oily fish
• Eggs
• Fortified vegan foods (milks, ‘cheeses’ and margarines)

Vitamin boosts – supplements and injections

Your dietitian will probably recommend that you take some nutritional supplements, at least for a short period. Avoid supplementing without specialist advice, never assume you can compensate for omitted foods with vitamin pills, and don’t use supplements as substitutes for skipped meals. Always verify that supplements are free from gluten – your dietitian can advise. Never take additional supplements without letting your dietitian know.

In more serious cases of deficiency, injections of vitamins – for instance, of vitamins B12, D or K – may be recommended.

Weight management

‘Classical’ coeliac disease patients are often underweight, but these days ‘atypical’ forms of coeliac disease are more commonly encountered among those newly diagnosed, and it is being realized that many patients are of average weight – or even overweight – at diagnosis.

Once established on a healthy gluten-free diet, many coeliacs start to put on weight. This should be generally interpreted as a healthy sign: the gut lining is healing, and becoming more efficient at absorbing nutrition and therefore calories. With health improvement comes appetite improvement, further driving caloric uptake.

But if you are overweight, or if you become overweight, it is a cause for concern, as this can have implications on long-term health and increase your risk of type 2 diabetes and cardiovascular disease.

There is a wide perception that the gluten-free diet is automatically healthy, largely as a result of celebrities in the media, who speak about having lost weight after giving up gluten. In the everyday world, this is not necessarily the case.

There are obviously steps you can take to control your weight, or lose weight if you need to, and your dietitian can advise. He or she will probably recommend at least light to moderate exercise: activity is hugely important.

Low glycaemic index foods

The glycaemic index (GI) of a food is a measurement of how it affects your blood sugar levels.

Some foods, those with high GI scores, are digested quickly by the body and so increase blood sugar levels rapidly. In an attempt to ‘normalize’ these levels, your body releases large quantities of the hormone insulin into the blood. But this can cause a sudden ‘dip’ in blood sugar, leaving you hungry and lacking in energy. And the result is you eat more.

Instead, many dietitians recommend that you should concentrate on foods with moderate to low GI scores. These tend to be those that your body has to work harder to break down, and that therefore release energy into the blood slowly. These foods are more sustaining and satisfying over a longer period, making it less likely you’ll be tempted to eat between meals or make your subsequent meal a larger one than needed, helping with weight control.

High GI foods

These should be consumed in moderation, and include white rice, baked potatoes, sugars, sweets, refined gluten-free cereals, GF treats, white bread and chips or crisps.

Moderate GI foods

These include whole grains (e.g. quinoa, brown rice), GF muesli or oats, GF pasta, new potatoes, sweetcorn and a few fruits.

Low GI foods

Examples include brown gluten-free breads, all pulses and lentils, nuts, seeds, dairy produce, most vegetables and many fruits.

Notable from these lists is the high GI value of some of the default GF staples that people typically turn to when diagnosed: white rice and baked potatoes. This is why it’s important to incorporate non-gluten grains into your diet.

Fibre

There is some evidence that coeliacs eat less fibre than non-coeliacs, and that some gluten-free replacement food is lower in fibre than the regular food. Fibre adds bulk and ‘fill’ to the diet, helping with weight control. Some tips:

• Choose whole grain GF cereals with, for instance, amaranth and millet.
• Go for brown versions of GF pasta, breads and pizza bases if you can.
• Whole grains such as brown rice, buckwheat and quinoa are important sources of fibre.
• Flours made from gram or chickpea and buckwheat, for example, are more fibre-rich than ordinary GF white flours.

If boosting your fibre intake, remember to keep up your fluid intake.

Sweet treats

Some research indicates that adult women with coeliac disease have a slightly higher average energy consumption than non-coeliac women, and that this difference is due to sugars in the diet. It is possible that women may be more likely to ‘treat’ themselves or to overcompensate for the restrictions of a GF diet with more sweet foods. ‘Free-from’ sweet foods may be more calorific.

Obviously, you need to moderate your intake of sweet and high-fat and calorific treats, which should make up no more than 7 per cent of your daily intake. This means a small piece of GF cake or a few GF biscuits. It’s better to restrict them to after a meal, so they don’t cause a steep rise in your blood sugar levels. Of course, for occasions, you can enjoy (a little) more.

Weight loss

Weight loss is possible if, as a newly diagnosed coeliac, you find the gluten-free diet difficult, unpalatable or depressing. Some people feel wary or suspicious of consuming prescription foods made from Codex wheat starch, or even safe foods, so closely do they relate their diet to their ill health. Understandably, many are frightened of eating out.

Your dietitian will address this with you if he or she notices a problem, but speak to him or her if these feelings are familiar. Your dietitian can also help to reassure you of the safety of GF products, increase your confidence and understanding of food labelling so you can choose food confidently, and introduce you to alternative foods, with advice on recipes. A gluten-free cookbook can also inspire you.

Here are some ideas to boost calorie intake in a healthy way via energy-dense, naturally wholesome foods:

• Add seeds and crushed nuts to yoghurts and salads.
• Fortify smoothies with protein powders (e.g. hemp, flax).
• Add rich cheeses, olives and avocado to salads.
• Enrich soups with cream or grated high-fat cheese.
• Stir chopped dried fruits into GF oat porridge.
• Avoid diet or low-calorie products such as diet colas.

Probiotics

Billions of bacteria live on the lining of your gut. Weighing in total around a kilogram, these bugs keep your immune and digestive systems working well, and help you to digest and absorb vital nutrients, as well as neutralizing any toxins. These so-called ‘good’ bacteria – or probiotics – also ward off ‘bad’ bacteria – the pathogens that can cause infection and poisoning.

Research suggests that those on the gluten-free diet have slightly poorer populations of gut bacteria, and that coeliacs are more likely to have an overgrowth of non-beneficial bacteria in the gut, which could be responsible for ongoing symptoms.

Because modern diets contain few naturally occurring probiotics, there is now a range of food products fortified with them. These include yoghurt products and milk drinks.

The most common probiotics on the market are from the Bifidobacter and Lactobacillus families, which some experts have suggested offer us better general benefits than other bacterial families and which also seem able to survive the acidic environment of the stomach and the various digestive processes, to reach the large bowel, where they are needed. Studies suggest that they can help to reduce bloating, speed up a sluggish digestive system and support the immune system, but it is becoming increasingly clear that different probiotics have different qualities and can help with different conditions.

There has been some modest research on the possible benefits of probiotics in coeliac disease. A Finnish study published in 2008 found that the probiotic Bifidobacterium lactis could counteract the toxic elements of wheat gluten and possibly inhibit them from triggering damage to the gut lining. Researchers suggested that probiotics could have value in accelerating gut healing after beginning a gluten-free diet, and perhaps even serve as an ongoing protective mechanism against coeliacs’ almost inevitable low-level gluten intake.

A Spanish study from 2010 found that Bifidobacter probiotics may offer strong anti-inflammatory benefits to the coeliac gut.

Even though the case for probiotics is far from proven, there is unlikely to be any harm in boosting your diet with them. Supplements are available, but dietary sources include:

• Live yoghurts
• Fortified yoghurt drinks and fermented milk drinks
• Sauerkraut Miso (check that it is rice or soya miso, not barley miso)
• Tempeh

Prebiotics

Whereas probiotics are bacteria which promote health, prebiotics are indigestible carbohydrates, naturally found in some foods, which feed those friendly bacteria already in your bowel and encourage their proliferation.

A fruit- and vegetable-heavy diet will be richer in prebiotics than a processed- or meat-heavy diet. The known prebiotics are fructo-oligosaccharides (FOS), inulin and galacto-oligosaccharides (GOS). They are found generously in chicory and Jerusalem artichokes, and to a lesser degree in garlic, onion, leek, asparagus, gluten-free oats, beans and bananas. Resistant starch is thought to have prebiotic properties too.

Resistant starch is a type of starch that is not fully digested in the small intestine and that reaches the large intestine where it becomes available to probiotics. It occurs in cooked cold potatoes, green bananas, cold brown rice, beans, pulses, oats and yams.

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