Finding yourself suddenly beset by odd symptoms after meals is both unpleasant and uncomfortable, and a food intolerance may not be the first explanation that comes to mind. We tend to think of food intolerance as a lifelong condition – something you are born with. This is sometimes true, but the development of sudden food intolerance in adulthood is far more common than people realise.
Unlike food allergies, which involve the immune system, food intolerance is a digestive disorder. The symptoms are triggered as our bodies attempt to break down and absorb particular foods.
Some of the commonest of these symptoms include:
- Stomach pains and cramps
- Gas and bloating
Of course, the severity of these symptoms and the precise mix varies from person to person.
What causes sudden food intolerance?
Food intolerance has a variety of causes. Some, like lactose intolerance, are genetic in nature – lactose intolerance is a good example of this category. Lactose is a milk sugar and digestion of this substance requires the enzyme lactase. But lactase production ceases after early childhood in most people across the world. Why? Because they have been weaned. Lactase production into adulthood requires a particular combination of genes and this is limited to certain populations who have been consuming dairy foods over a long period of time.
But these are the exceptions. Most food intolerance reflects the person’s overall state of health. Healthy gut flora levels can be diminished and the inner lining of the stomach damaged by:
- An unhealthy diet
- Overindulgence in alcohol
- Some pain-killing medicines
- Anxiety or stress
- Infection or illness
This damage develops over time, encouraging inflammation and interfering with digestion. In most instances, a ‘sudden’ food intolerance will only appear to be sudden and will in fact have been developing for months, or even years.
Molecules of poorly digested food may sometimes escape the stomach, attracting the attention of the antibody immunoglobulin G (IgG). This is called ‘intestinal permeability’ or ‘leaky gut syndrome’. Over time, these antibodies may begin to respond to particular foods. Next stop: a chronic food intolerance.
These problems can develop at almost any age. Everyone is different – with differing genetic propensities and varying levels of health. So one person might struggle with fruit, another with dairy, and a third with wheat. Some people can consume small quantities of their problematic foods without symptoms, while others begin to feel ill after a single bite.
How to find out what you’re intolerant to
Working out exactly what you’re intolerant to may not be a straightforward affair. If you eat a boiled egg and immediately feel ill, then the link will be obvious, but what if you’ve eaten a whole breakfast before the queasiness begins? Some people do experience immediate symptoms but they can – unhelpfully – be delayed for hours.
If you have strong suspicions then an elimination diet can be an effective method of finding out for sure. Remove all the candidate foods from your diet, reintroduce them one by one and wait for the onset of symptoms.
Armed with this knowledge, you will be able to adapt your diet, minimising exposure to the foods that cause you problems. That might mean cutting them out altogether or it might mean simply cutting down.
Another way to feel better is to eat more foods that promote healthy digestion. Both sugar-free, probiotic yoghurt and fermented vegetable products such as sauerkraut and its Korean counterpart kimchi have been linked to improved gut health. Add these to your shopping list and consume them regularly. Your stomach will be happier.
Longer term the news is often good. Unlike allergies, many food intolerances are temporary. Take a break from the foods that cause you problems, work on improving your health and overall diet, and you may well be able to reacquaint yourself with bread, cheese, fruit, fish or whatever else at some point in the future.
Written by Bev Walton, BSc Nutritional Science
I achieved a First-Class Honours degree in BSc Nutritional Science, Nutrition Sciences from the University of Reading and now have over 35 years experience in all types of cuisine, dietary plans, recipe development, health and nutrition. I have been writing for over 10 years for magazines and websites as well as ghostwriting for ebooks, Kindle and fully published books. I’m also a proud member of the Guild of Food writers.