Are there some foods you love that you vaguely suspect don’t love you back?
By Elaine Bracefield, BSc. Nutritional Biochemist & Genomic Wellness consultant.
Do you feel bloated after your breakfast cereal in the morning? Feel like you experience wind after eating bread? Do you develop an itchy rash whenever you eat something that doesn’t agree with you? Or might drinking coffee give you more than the usual buzz?
Many of us have food sensitivities that we aren’t even aware of. Causing unknown havoc in our bodies.
Food intolerances are complex, and it is often difficult to pinpoint the exact food which is causing the problem. But if we can work out exactly which foods we might be intolerant to, we’ll be able to improve how we feel each day.
Reducing our intake of these foods, or omitting them from our diet entirely, is a quick and extremely effective way to instantly boost our health and wellbeing.
Before DNA testing was available, working out which foods we might be sensitive to was a slow and painful process. We’d go on a total elimination diet and strip back to eating just plain white rice, and then gradually introduce other foods, whilst keeping a detailed food diary of how our body reacted to those new foods brought in. Many people would start the process of food elimination with the best intentions, but after a month or two – abandon it as all too hard.
These days, however, our genes offer us an easy shortcut to working out exactly how our digestion works.
Our individual genes have a critical role in how well we tolerate dairy products.
Some people adore dairy products and never have any ill effects from eating them. Others, however, may suffer from stomach pains, loose stools, diarrhoea or rashes after consuming milk, yoghurt or cheese. These kinds of symptoms may be the clearest sign of lactose intolerance – an inability to digest the sugars found in milk and dairy products. Due to not producing enough of the enzyme lactase, which is responsible for breaking down lactose.
A genetic variation in the LCT (lactase) gene, called MCM6, enables the detection of lactose intolerance. It is rare for the lactase enzyme to be totally absent – most people produce some lactase so this means they can tolerate a certain amount of milk products in their diet, but when their threshold is reached that is when symptoms will likely appear.
When the lactase enzyme production is low, the body is unable to break down lactose, and this unused lactose is then digested by resident bacteria in the colon. Resulting in symptoms such as bloating, flatulence, diarrhoea or cramps in the abdominal area. A genetic test for lactose intolerance is a good idea if you are experiencing any of these symptoms and don’t know why.
Are we all gluten intolerant?
True gluten intolerance manifests as coeliac disease, a medical condition where the body reacts badly to gluten (a protein found in wheat, rye and barley) which damages the small intestine and can hamper the absorption of nutrients in the body. This leads to chronic vitamin deficiencies, which if untreated can lead to very serious health problems.
Symptoms of the illness include pain and discomfort in the digestive tract, constipation, diarrhoea and fatigue. Organs may also be damaged. For children, the condition may cause failure to thrive and stunted growth.
Coeliac disease is often inherited and your genes are a known risk factor. Around 99% of people with coeliac disease have either of the risk genes HLA-DQ2 or HLA-DQ8 or a combination of both. HLA genes are part of your immune system that distinguishes foreign proteins from your own proteins, and if you have coeliac disease then your body reacts to gluten found in wheat, barley and rye.
Genetic testing will identify if you have inherited these HLA risk genes. If you have neither of these HLA genes then you are very unlikely to have or develop coeliac disease. If you do have one or both risk genes, then there is a much higher chance of developing the illness. The gold standard to confirm if you do have coeliac would then be to follow this up with a small bowel biopsy.
Are you a fast or slow caffeine metaboliser?
Caffeine is one of the most popular stimulant drugs in the world. Mostly consumed in coffee, tea, soft drinks and energy drinks like Red Bull as well as in chocolate. Research has shown that doses of caffeine over 300mg (or three cups of coffee per day) can be unhealthy and damaging to the brain. As a stimulant that directly affects the central nervous system, it can also put significant strain on the heart, liver and kidneys. Too much caffeine can make you feel restless, anxious and irritable; it can interrupt sleep and cause headaches.
Many people become caffeine dependent over time and if they stop using it, they can experience unpleasant withdrawal symptoms. The gene CYP1A2 is the one needed in the liver to break down up to 95% of the caffeine in the body. Some people might not have this gene, it might be defective or other genes may be working to undermine it. Thus, these individuals are likely to be much more sensitive to caffeine than the average person. Signs there may be a problem are feelings of anxiety, rapid heart rate after consuming caffeine or problems falling asleep.
A genetic test can tell if you are a fast or slow metaboliser of caffeine. If you are a slow metaboliser then the stimulant effects last longer in your body and you’ll need to either cut out coffee or at least restrict your caffeine intake to one or two cups per day. Double that and you’ll also double your risk of a heart attack.
Getting your DNA test is a good idea if there’s a family history of high blood pressure or heart disease, or if you are overweight or have high cholesterol. Knowing whether you are sensitive to caffeine is particularly important for women planning a pregnancy as caffeine metabolism is further impaired during pregnancy. Being forewarned with this personal health information will protect against a host of illnesses for both mother and baby.
In summary, getting your DNA tested will reveal exactly how well or how poorly your body deals with foods such as lactose, wheat, gluten, caffeine and salt.
Understanding your genetic ability to process these foods and then either decreasing the amount you eat or cutting them out entirely and substituting alternatives for them, will not only help you feel better every day but may also help to substantially reduce your risk of developing other diseases.