DR MEGAN ROSSI: Are chemicals added to food making YOU ill?

Just how worried should we be about food additives such as emulsifiers, preservatives, colours and artificial sweeteners?

In the past, the additives used in food were essentially pretty simple — think of salt, used to help store food for longer.

But these days, pick up any processed food, from biscuits to curry sauce, and the list of chemical additives in it may exceed the ingredients you actually recognise as food. But are they bad for us?

Some people are definitely sensitive to certain food additives.

One of the most common sensitivities is to sulphites, which are primarily used as a preservative — you find them in foods including dried fruit; jams and dips such as guacamole; processed meats; fresh and frozen crustaceans such as prawns; as well as drinks, including soft drinks, cider, beer, wine and cordials. (Check labels for additive numbers E220-228 and E150b and 150d or names such as sulphur dioxide, sodium sulphite and sulphite ammonia caramel.)

People with eczema and asthma seem to have a higher sensitivity to sulphites — one theory is they stimulate the nerves involved in breathing and irritate the respiratory tract.

The symptoms are not just gut specific — sufferers can experience hives, swelling, wheezing or a stuffy nose. Bad hangovers, too, have been associated with sulphites in wine.

These days pre-packed food sold in the UK must by law show clearly on the label if it contains sulphites above 10mg per kg or per litre.

Another problem is sensitivity to salicylates, which cause similar symptoms.

Salicylates are found naturally in herbs and spices, such as black pepper and cumin; in fruits, such as apples, strawberries and kiwi; and veg including asparagus and sweetcorn.

They are also in many drinks such as coffee, black tea and apple juice. If you’re concerned about dietary salicylates, it is best to see a dietitian as the amount can differ based on processing and season, making it risky to try to tackle it alone.

Then there are, of course, the food colourings linked to hyperactivity in some children, which is why the Food Standards Agency (FSA) has ruled that food and drink containing any of these six colours — sunset yellow (E110), quinoline yellow (E104), carmoisine (E122), allura red (E129), tartrazine (E102) or ponceau 4R (E124) — must carry a warning.

But some sensitivities may not be quite what they seem — following reported concerns about sensitivity to aspartame (e.g. headaches, dizziness and stomach upsets), the FSA commissioned research to investigate.

The study, published in 2015, showed that there was no difference in reported symptoms after eating an aspartame-containing cereal bar compared with a bar without aspartame.

If you don’t have a sensitivity to any food additive, should you worry about all these chemicals in our food? There are more than 300 additives that have been authorised by the European Food Safety Authority (EFSA) for use in food, which means they’ve undergone a rigorous safety assessment.

However, in 2008 the EFSA declared that all food additives authorised for use in the EU prior to 2009 must be re-evaluated for their safety. This has resulted in a number of changes. For example, from last week titanium dioxide (E171), a colouring added to sweets and baked goods, is no longer allowed in the EU and Northern Ireland (though it’s still used in the rest of the UK).

Despite this re-evaluation, many of the safety assessments haven’t considered the impact on our gut microbes that play such a key role in our health. That’s because a lot of these assessments were undertaken before we understood the importance of these microbes.

Some animal studies have shown that certain types of artificial sweeteners, such as sucralose, saccharin and aspartame, have a negative effect on our gut microbes, including a raised blood sugar response to food, liver inflammation and weight gain.

In human research, the evidence is not as strong, with conflicting results about artificial sweeteners and gut health. These different findings are likely explained by the fact that we all house different microbes which can respond in various ways.

For instance, one very small, but important, study in Nature showed that daily intake of saccharin for one week negatively impacted blood sugar responses in four out of seven people tested.

Other additives to flag up are nitrates and nitrites. Our bodies naturally convert nitrates found in food such as spinach and beetroot into nitrites and then nitric oxide, which helps dilate the blood vessels. This is good for lowering blood pressure, a risk factor for heart disease.

However, the nitrites and nitrates added to food — in particular, to processed meat such as sausages — can be converted into nitrosamines, which can be carcinogenic (cancer-causing). Other additives, including stabilisers, thickeners, gelling agents and emulsifiers found in a wide range of processed foods — particularly frozen desserts, dairy-free milks, cakes and biscuits — have also been implicated in inflammatory bowel disease.

Our research team at King’s College London are investigating this with a world-first food-additive randomised control trial — where we’re testing a low food additive diet in people with active Crohn’s disease.

This is based on research suggesting it can lead to an inflamed gut in genetically susceptible people. If you have active Crohn’s, live in the UK and would like to take part in the study, email ADDapt@kcl.ac.uk to find out more.

There are still many unknowns in the food additive arena. But while we’re busy trying to understand the interactions, limiting additives where you can is a good approach for now.

Really this just reinforces what most of us inherently know: home cooking using whole foods is always a better option.

With packaged foods, check the ingredients list and if you see more than one E-number (often written out in words that don’t sound like food), you might want to consider if it’s right for you.

As for fizzy drinks, try flavouring sparkling water with frozen berries and mint the next time you’re craving a soda.

Try this: Choc chip courgette cookies

My answer to those biscuit cravings: high-fibre choc- chip cookies — and the kids won’t taste the hidden veg!

Makes 18 cookies

• 1 ripe banana (approx 100g)
• 6 Medjool dates, pitted and roughly chopped
• 50ml extra-virgin olive oil
• 150g whole oats
• 2tsp vanilla extract
• 1 courgette, grated (140g)
• 60g dark chocolate chips

Preheat oven to gas mark 4 and grease two baking trays. Place the banana, dates and olive oil, vanilla and half the oats in a blender and blitz to a paste.

Squeeze grated courgette in a clean cloth to remove the moisture, then add to a mixing bowl, with the chocolate chips and the remaining oats. Then add the blended contents of the food processor.

Stir well to combine into a thick mix. Spoon on to the baking trays, making 18 cookies, and gently smooth into flat rounds.

Bake in the oven for 25 to 30 minutes, or until golden brown. Transfer to a wire rack and leave to cool.

AskMegan

I had a hiatus hernia repair two years ago and since then I get terrible bloating and constipation, and gas builds up in my chest and throat, making it hard to breathe until I can belch (which can take hours). I’ve been diagnosed with dysphagia [difficulty swallowing]. I use lactulose [a laxative] a couple of times a week.

Maxine Naden, by email.

I was sorry to hear about your gut symptoms post-surgery. It sounds like the priority should be getting on top of your dysphagia, as you may find that is the culprit triggering the bloating and constipation. 

This is because when people have swallowing issues, they typically change their diet to accommodate, which can mean lower fluid intake and more soft, processed foods.

I would recommend talking to your healthcare team about seeing a speech and language therapist who can teach you exercises to help rebuild and refine your swallowing muscles and mechanics.

They can also advise on whether you would benefit from thickening your fluids to ensure you’re staying hydrated — a common cause of constipation and bloating.