Our bodies need a variety of vitamins and minerals to stay healthy and calcium is one of the minerals that is crucial to our overall wellbeing.
To keep it simple, calcium aids our bodies in building and maintaining strong bones and teeth, while also helping to keep our nerves and muscles in tip top condition. If that wasn’t enough, calcium also ensures our blood clots normally, so it really is an important mineral to include in our diets during every stage of life.
During childhood and adolescence, calcium is essential for the formation of strong, healthy bones and teeth and in fact, 90% of our bone strength is achieved before the age of 18 in girls and before 20 years in boys!
During the teenage years bones will continue to grow and develop until around the age of 25 when they reach their “peak bone mass” and this highlights just how important it is that your little ones are reaching their calcium intake throughout these critical stages of life.
Daily Guideline Amounts of Calcium:
Below I have included a table produced by the British Dietetic Association (BDA) which states how much calcium should be included in the diet from infancy all the way into adulthood, as well as during breastfeeding when the requirements increase dramatically.
Table 1: Calcium Recommendations from the BDA
Calcium during Pregnancy and Breastfeeding:
During pregnancy and breastfeeding, as baby’s need for calcium increases, a mother’s body adapts to increase the amount of calcium provided to a growing baby. This includes increased absorption rates as well as stores being drawn from the mother’s bones to supply extra calcium needed. During lactation, calcium needs are met by changes in a mother’s body including reabsorption of calcium from a mother’s bones. Breastfeeding mums also produce less oestrogen – a very important hormone that protects our bones. Therefore, it is no surprise that breastfeeding mums need quite a lot more than the average, healthy adult.
In fact, studies have shown that women often lose 3 to 5 per cent of their bone mass during breastfeeding (this is rapidly recovered after breastfeeding is stopped!)
What foods can I get calcium from in my diet?
Luckily, we are fortunate enough to find calcium in a whole range of foods in the UK. These range from dairy products such as milk, cheese and yoghurt to fruit and veggies such as broccoli, spring greens and oranges. You will also find that a lot of cereals, bread and even orange juice are fortified with calcium – not all of them though, so it is worth checking the label!
Milk alternatives that have been fortified contain around 240mg of calcium and these are good alternatives for individuals that can’t or don’t want to include dairy in their diet. Fortified milk alternatives can still provide a really good source of calcium as part of a balanced diet, along with other important vitamins and minerals too. If you’re unsure what the deal is when it comes to non-dairy milks for toddlers and children, check out my blog on Plant-Based Milks for Infants and Toddlers.
Included below are tables from the BDA which show the range of foods that can provide good sources of calcium for all ages!
The British Dietetic Association (BDA) have produced a really creative way of checking how much calcium you and baby are getting from your diet and how you can include more called the ‘calcium stars’ system. For more information or to check it out, see the link to the BDA factsheet at the bottom of this blog.
Table 2, 3 and 4: Sources of Calcium, from the BDA
Calcium deficiency:
Although calcium deficiency is rare, you may be more at risk if one or more of the following applies:
- You are on a cow’s milk or lactose free diet
- You have coeliac disease
- You have osteoporosis
- You are breastfeeding
- You are past the menopause
A lack of calcium in the diet could lead to rickets in children and osteoporosis in adults. Rickets had mostly disappeared during the early 20th century however recently, an increase has been seen in the number of cases in the UK possibly due to low levels of Vitamin D. Symptoms of calcium deficiency can include dental problems, poor growth and fragile bones – if you are worried this may apply to you or your child, please do see your GP.
Calcium Supplements:
If you are finding it hard to meet your daily requirements of calcium from the food in your diet, your doctor may advise you to consider taking calcium supplements. These are easily available from most pharmacies and supermarkets – you may also qualify for Healthy Start supplements which you can get free from the UK Government – ask your Health Visitor or GP for more details.
The NHS state that taking supplements of up to 1,500mg a day is unlikely to cause any harm however taking doses higher than this may lead to diarrhoea and stomach pain. It is unlikely that you’ll consume too much in the way of calcium from food sources, however it is not impossible. Check any supplements you’re taking with GP if you’re concerned or to avoid any unpleasant symptoms.
Calcium absorption factors:
On the whole, the calcium absorbed from a mixed diet is relatively constant at around 25-35% absorption and in fact, there are a few components of our diet that can enhance or even inhibit this absorption of calcium from our foods!
For example, the presence Vitamin D really helps the body’s ability to absorb calcium effectively. In the UK it is recommended that we take a vitamin D supplement of 10ug per day, especially in the winter months where we have limited access to sun.
There are also naturally occurring molecules such as oxalate and phytate in our food, specifically in plant-based foods, which can inhibit the body’s ability to absorb calcium. Oxalates and phytates can be found in a variety of food sources such as spinach, beans, nuts and seeds. Oxalate molecules can bind to the calcium in the digestive system and alter how much calcium is actually absorbed.
However, these are not a major concern for most people, as long as you’re following a healthy, balanced diet including foods from all the main food groups (or fortified alternatives) you should be able to get enough calcium.
On the other hand, for those on a plant-based diet or for whom calcium deficiency is a risk, it may be worthwhile checking out the best sources of calcium to include in your diet.
What about vegans?
It is really important that calcium intake is carefully considered if you are thinking of adopting a vegan diet. Since most non-vegans get their calcium from dairy foods, it can be a little bit more challenging for vegans, but it can be done!
Below is a list of foods that are a good source of plant-based calcium. You can read more about this on the NHS website as well as the Vegan Society Calcium Factsheet.
Food sources of calcium for vegans:
- Fortified unsweetened soya, rice and oat drinks
- Calcium-set tofu (100g can provide half of an adult’s daily needs, according to the vegan society!)
- Seasame seeds
- Pulses
- Brown and white bread (since they have both been fortified with calcium)
- Dried fruit e.g raisins
In fact, according to the Vegan Society, around 400ml of calcium-fortified milk alternatives provides roughly two thirds of an adults recommended daily intake of calcium!
When it comes to the most easily absorbed calcium sources from a plant-based diet, these include:
- Fortified soya milk
- Most sources of tofu
- Fortified orange juice
- Chinese vegetables such as bok choy
- Kale
- Broccoli
- Sprouts
Take home messages:
Calcium intake is super important during childhood and teenage years and it is really essential to ensure your child is meeting recommended intakes to give them the best chance of developing strong and healthy bones that will last them a lifetime!
- You may be entitled to free calcium supplements if you are eligible for Healthy Start vouchers, so it is worth finding this out.
- A lot of foods and beverages have been fortified with calcium and can be a really good way of ensuring you reach those daily requirements but make sure you do check the label.
Article written by Holly Roper MSc student University of Sheffield with support from SR Nutrition.
Useful Reading and References:
https://www.bda.uk.com/foodfacts/Calcium.pdf
https://www.nhs.uk/conditions/vitamins-and-minerals/calcium/
https://www.nhs.uk/conditions/rickets-and-osteomalacia/symptoms/
https://www.nhs.uk/live-well/eat-well/the-vegan-diet/
https://www.vegansociety.com/resources/nutrition-and-health/nutrients/calcium
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2854913/
https://www.bones.nih.gov/health-info/bone/bone-health/pregnancy#b
https://www.nutrition.org.uk/attachments/105_Dietary%20calcium%20and%20health.pdf