Have you got a gut feeling that lactose just isn’t for you? If you get pain, feel bloated or gassy after a few too many chocolates, you’re not alone. Approximately 65% of the world population have a reduced ability to digest lactose after infancy.
As symptoms of lactose intolerance can be similar to that of IBS (irritable bowel syndrome) and milk protein intolerance, it can be tricky to know which condition you have. In this blog we take a look at the causes and symptoms of lactose intolerance, which foods to avoid, as well as how to get the nutrition you need from a lactose-free diet.
What is lactose intolerance?
Lactose intolerance is a common digestive problem where the body is unable to digest lactose, which is a type of sugar mainly found in milk and dairy products.
What causes lactose intolerance?
Lactose intolerance can be caused by your body not producing enough lactase. Lactase is an enzyme (a protein that causes a chemical reaction to occur) produced in your small intestine that's used to digest lactose. There are several types of lactose intolerance: primary lactose deficiency, secondary lactose deficiency, congenital lactase deficiency, and development lactase deficiency.
Primary lactase deficiency
Primary lactase deficiency is the most common type of lactose intolerance and is genetically inherited.
When we’re born, we’re able to produce plenty of lactase to manage the amount of milk in our diet. As we grow older and we become less reliant on milk and dairy, our body gradually decreases the amount of lactase produced whilst remaining high enough to digest the amount of dairy in a typical adult diet.
However, for people with primary lactase deficiency, their lactose production rapidly declines, making milk products difficult to digest by the time they reach adulthood.
Secondary lactase deficiency
Secondary lactase deficiency is a shortage of lactose caused by a problem in your small intestine.
It can occur at any age and may be the result of another condition, surgery (to your small intestine) or taking certain medications, including gastroenteritis, coeliac disease, Crohn's disease, ulcerative colitis, chemotherapy and long courses of antibiotics.
By treating the disorder itself, the levels of lactase may restore to their usual levels as well as improve the symptoms of lactase deficiency.
Congenital lactase deficiency & development lactase deficiency
Some babies can be born with very little to no production of lactase. This can be caused by congenital lactase deficiency which is genetically inherited or development lactase deficiency, which can occur in prematurely born babies. For more information on lactose intolerance in babies, please see the NHS website.
Foods and drinks containing lactose
There are a variety of food and drinks containing lactose, including some products that you wouldn’t usually expect, such as salad dressing, biscuits and boiled sweets. The main culprits are usually dairy products including:
- Ice cream
I don’t brie-lieve it!
Not all cheeses contain lactose. Cheese is made by adding bacteria or acid to milk and then separating the cheese curds from the whey. Lactose is found in the whey, so a lot of it’s removed in the cheese-making process. That’s great news if you’re mad about cheese! Hard cheeses tend to be lower in lactose, so think cheddar, parmesan and aged cheeses. Higher lactose cheeses tend to include cheese spreads, soft cheeses like brie or camembert, cottage cheese and mozzarella.
🧀 Next time you’re at the shop, check out the nutrition label on your favourite cheese. Lactose is sugar, so if the label says 0 grams, then it’s probably low-lactose.
What are the symptoms of lactose intolerance?
There are several different symptoms of lactose intolerance and the severity of the symptoms will vary depending on how much lactose has been consumed and your level of intolerance. Symptoms will begin to show between 30 minutes and 2 hours of the lactose being consumed with the most common symptoms being;
- Upset stomach
Is it in your genes?
The lactase enzyme that helps to break down the sugar (lactose) found in milk and dairy is made from a gene called LCT.
The LCT gene is connected to the instruction making gene MCM6.
Within the MCM6 gene is an SNP (single nucleotide polymorphisms), which controls whether the lactase enzyme is active or inactive. This affects whether a person is lactose tolerant or intolerant in adult life.
Finding out if you’re lactose intolerant can be painstakingly slow, especially if you’re using the trial and error method of cutting out dairy from your diet to see if your symptoms improve.
Listen to your gut
With genetic testing, you can see whether you do or don’t have the LCT gene associated with lactose intolerance.
If you think you are extremely sensitive to lactose, talk to you GP about your diet. You can book an appointment with your GP using the Evergreen Life app.
Deficiency risks with lactose intolerance
Milk and other dairy products contain calcium, protein and vitamins, which are important for a strong and healthy body. Lactose helps your body absorb these vitamins and nutrients so being lactose intolerant means it can be tricky to get the right amount in your diet. This can increase your risk of developing conditions such as osteopenia, osteoporosis and malnutrition. However there are a variety of products which contain the nutrients you need and are lactose free.
Maintaining good nutrition with a lactose intolerant diet
Avoiding or eating fewer products containing lactose can mean you miss out on certain vitamins and minerals that are crucial for a healthy diet. How much you cut out may also depend on how intolerant you are. Fortunately you can get the nutrition you need from other lactose free products including non dairy healthy sources of fat, non dairy sources of calcium and non dairy sources of vitamin D.
If you’re unable to eat most dairy products then you’ll most likely not be getting enough calcium in your diet. Calcium has several important functions including building strong teeth and bones, regulating muscle contraction (including the heartbeat) and ensuring blood clots normally. Adults aged 19 to 64 need 700mg of calcium a day. Some non-dairy sources of calcium include:
- Leafy green vegetables, such as kale, broccoli, cabbage and okra
- Soya beans
- Bread and anything made with fortified flour
- Fish containing edible bones (for example, sardines, salmon and pilchards)
But - if you’re lactose intolerant, you’ll also have to watch out for your vitamin K2 intake. This nutrient is essential for funnelling calcium into your bones. But grass-fed dairy is one of the richest sources of vitamin K2; so, cutting out dairy means that you’ll need to find other sources to achieve your body’s needs.
To get your vitamin K2 levels up, try incorporating chicken liver, minced beef, or some eggs (specifically the yolk) into your diet.
A fat load of good
We need a small amount of fat for a healthy, balanced diet as its a source of essential fatty acids, which the body can’t produce itself. Fats helps our bodies absorb vitamins A, D and E as well as being used for energy. Some non dairy sources of fat include:
Top up on the sunshine vitamin D
Vitamin D helps regulate the amount of calcium and phosphate in the body. These nutrients are needed to keep bones, teeth and muscles healthy. Children from the age of 1 year and adults need 10 micrograms of vitamin D a day. Some non dairy sources of vitamin D include:
- Oily fish – such as salmon, sardines, herring and mackerel
- Red meat
- Egg yolks
- Fortified foods – such as most fat spreads and some breakfast cereals (just watch out for the sugar content!)
Discover the inner you and order your DNA test today.
US National Library of Medicine, (2019) "Lactose Intolerance," Genetics Home Reference [online], Available at: https://ghr.nlm.nih.gov/condition/lactose-intolerance#statistics
NHS, (2018) "Lactose intolerance," NHS [online], Available at: https://www.nhs.uk/conditions/lactose-intolerance/.
Cafasso, J. (2016) "What causes lactose intolerance?," Healthline [online], ed. N. Butler, Available at: https://www.healthline.com/symptom/lactose-intolerance.
Mayo Clinic Staff, "Lactose intolerance," Mayo Clinic [online], Available at: https://www.mayoclinic.org/diseases-conditions/lactose-intolerance/symptoms-causes/syc-20374232.
Kindstedt P.S. (2013) "The basics of cheesemaking," Microbiology Spectrum [online], Available at: https://www.ncbi.nlm.nih.gov/pubmed/26184823.
Gunnars, K. (2017) "10 high-fat foods that are actually super healthy," Healthline [online], Available at: https://www.healthline.com/nutrition/10-super-healthy-high-fat-foods#section4.