The low down on lactose
Much of our lives are marked by a free-flowing consumption of dairy: from breakfast porridges and morning lattes, dairy is present in many of the things we eat and drink. Dairy foods such as cheese, ice cream and yoghurts all contain milk, and consequently, varying amounts of lactose. Despite the popularity and pervasiveness of milk and dairy, lactose can cause a bit of a stir in some stomachs…
What is lactose?
Nutrition Australia explains lactose as the carbohydrate naturally occurring in all types of milk, including human milk.
How we digest lactose
When we consume milk products, our bodies call upon the enzyme lactase to break down and digest the lactose. Lactase splits the lactose into two smaller sugars, glucose and galactose (designed to provide energy to your body).
Lactose Maldigestion
When a person lacks the lactase enzyme to digest the lactose, they are said to have lactose maldigestion, which causes undigested lactose to pass through to the small intestine (where 90% of digestion occurs) and go straight to the colon. This is the breeding ground for bacterial fermentation of lactose; producing the acids and gas that may be responsible for abdominal pain, bloating or diarrhoea. The crucial thing to note is that lactose maldigestion does not necessarily result in symptoms of lactose intolerance.
Lactose Intolerance
As breast milk and cow’s milk is the primary source of nourishment for newborns, most people are born with the ability to produce lactase. The possibility of developing lactose intolerance later in life can be influenced by factors such as your genetics (Nutrition Australia reports those with Asian, African, South American and Australian Aboriginal heritage have a tendency to produce less lactase with age than those of Northern European descent) or reversible medical conditions such as malnutrition or gastrointestinal infections.
Recent Roy Morgan research has found that lactose intolerance is on the rise in Australian women, with women aged between 25 and 34 exhibiting the highest incidence of lactose intolerance (8.2%). Compared with the average Australian, people who are lactose intolerant are:
- 72% more likely to have osteoporosis
- 158% more likely to experience nausea
- 183% more likely to get diarrhoea
- 212% more likely to be vitamin deficient
- 421% more likely to suffer from digestive problems
It is important not to self-diagnose lactose intolerance; a simple medical test by your GP can clarify whether you are lactose intolerant. If it turns out to be the case, you can still build up your tolerance by starting with small portions of milk and gradually increasing consumption. Other alternatives like yoghurt and cheese are low in lactose and are often better tolerated than milk.
Calcium absorption
Calcium is a mineral essential to the growth and maintenance of your bones – almost 99% of the body’s calcium is found in the bones. The small amount of calcium left over is absorbed into the blood; contributing to the healthy functioning of the heart, muscles, blood and nerves.
Since the bones house the majority of your body’s calcium, the body will draw calcium from your bones for other parts of your body if there isn’t enough calcium coming from your diet. Osteoporosis Australia claims less than half of all Australian adults are having their daily recommended intake of calcium. The more calcium withdrawn from the bones to other parts of your body, the more your bone density and strength declines over time – increasing the risk of developing osteoporosis.
Recommended calcium intake for adults over 19 years is 1,000 mg per day. For older adults, this increases to 1,300 mg per day. For children, the recommended intake increases as they grow and experience bone development:
- 1-3 years: 500 mg per day
- 2-8 years: 700 mg per day
- 9-11 years: 1,000 mg per day
- 12-18 years: 1,300 mg per day.
The recommended daily intake for each age group also accounts for the calcium that the body loses and excretes. Factors that may affect calcium absorption can include excessive caffeine and alcohol intake or low vitamin D levels. Vitamin D’s role in bone health includes supporting the growth and maintenance of the skeleton and regulating the calcium levels in the blood. Low levels of Vitamin D can lead to bone and joint pain, vulnerability to falls and fractures in older people or impact children in utero.
Luckily, with the upcoming summer weather, most of us can increase our Vitamin D levels via exposure to sunlight (ultraviolet B). Osteoporosis Australia says a little over 30% of Australian adults have a mild, moderate and even severe Vitamin D deficiency. If you think you may be at risk of deficiency, you can determine your Vitamin D levels with a blood test from your local GP.
Milk alternatives
Dairy foods are a great option for calcium intake, but there are many other sources available. If a glass of milk, tub of yoghurt or a slice of cheese doesn’t tickle your tastebuds, you can try leafy greens like broccoli, bok choy and mustard cabbage or other vegetables like cucumber, celery or chick peas. Almonds, fortified tofu or soy based products and fish canned with bones are also rich in calcium.
Four of the most well-known dairy milk alternatives include soy, almond, rice and oat milks. Versatile enough to replace dairy milk in smoothies, coffee, baked goods, soups and sauces, those looking to try something different may want to have a taste of the aforementioned dairy milk alternatives.
Keep in mind that fortified milk products should not be used as complete substitutes to calcium –alternative milks often contain less calcium and protein than cow’s milk. It’s important for those forgoing dairy to actively incorporate calcium and protein into their diets through other sources. For infants and young children, please consult your paediatrician.
Looking for more information on your health and lactose? Please seek advice from a registered health care professional for diagnosis and answers to your medical questions.
