# Healthy eating habits/Increasing calcium and Vitamin D intake in office workers

Calcium is one of the most essential minerals recommended for the diet as it is involved various roles and processes within the human body. As well as the imperative role that calcium holds in bone and teeth mineralization, promoting strong and prosperous bones, calcium is also required for the maintenance of cell membranes, enzyme systems and hormone actions. Also, due to its role in nerve function activity and transmission, calcium is a responsible component of muscle contraction, such as that of the heart.
Vitamin D is both a vitamin and a hormone that works in tandem with calcium in the body performing similar functions. For calcium to function correctly it needs Vitamin D and vice versa. Vitamin D is involved in the absorption and metabolism of calcium and other micronutrients. Like Calcium, Vitamin D helps with bone and teeth formation and helps to maintain a stable nervous system and healthy heart. It also functions in immunity and regulating blood pressure.

## The Role of Calcium

Calcium plays an essential role in bone structure and maintenance, providing the body with its framework. Around 99 per cent of the body’s calcium is stored in bones and teeth and the remaining 1 per cent can be found circulating in the blood and in cells. The calcium existing in the blood is tightly controlled and the bones provide a readily available source of calcium when body is in need. This means that when blood-calcium levels drop, the blood ‘borrows’ calcium from the bones to restore it to an appropriate level. When blood-calcium levels increase, the blood will ‘return’ any excess calcium back to the bones. Therefore, when calcium intake is consistently inadequate, calcium stores in the bone become depleted. This results in weaker bones which are susceptible to [Osteoporosis]. It is extremely important to consume adequate amounts of calcium-containing foods to ensure strong and healthy bones.

## What Constitutes A Serve?

The Australian Guide to Healthy eating recommendations (AGHE) 2 1/2 serves of dairy like milk, yogurt and cheese (mostly reduced fat alternatives) every day for people aged 19-50 years old and this is the same for both males and females. This equates to 1000mg of calcium per day.

### Calcium Serve

Sources of calcium can be either dairy or non-diary, so even a vegan or someone who just doesn't like dairy products can ensure they meet their daily requirements.

#### Dairy Sources

* 80g of cheese (2 slices) - Cheddar, Swiss or ricotta
* 1 cup of Milk
* 3/4 cup of yogurt

#### Non-Dairy Sources

* 1 cup of green leafy vegetables e.g. kale, bok choy, spinach or silverbeet.
* 15g of chia seeds
* 1/4 cup of almonds

### Vitamin D Serve

The best source of Vitamin D is of course, the sun! To ensure adequate Vitamin D intake each day it is good to spend at least 20-30 minutes in the sun each day.
Foods rich in Vitamin D include:
* 90g of cooked salmon
* 90 of sardines (including bones)
* 1 egg

## Tips For Extra Vitamin D

* Coming into work earlier or staying back a little later to walk around the block if the sun is out
* Walk around the office block during the lunch break
* Eat lunch outside

## Interactions and Interferences

Some nutrients aren’t absorbed as well if taken with calcium. Calcium can reduce iron absorption by as much as 50 percent. However, calcium only interferes with non-heme iron, which comes from plant-based foods, not with heme iron, found in meat.
When it comes to calcium, fibre also binds to the mineral, reducing its absorption. Studies have found that wheat fibre reduces calcium absorption by about half. If you are the type of person who aims to get a jump-start on fulfilling their recommended daily intake of fibre and calcium with your bowl of breakfast cereal, choose cereals primarily oats or other grains since they do not seem to block the absorption calcium.

## Supplementation & fortification

Sometimes, depending on the levels of calcium and Vitamin D in the body, it may be necessary take a supplement. Before using any supplementation it is important to refer to a doctor first.

## Reference List

* Kouris, A. (2012). Food Sources of Nutrients: A Ready Reckoner of Macronutrients, Micronutrients and Phytonutrients. Dr Antigone Kouris-Blazos.
* National Health and Medical Research Council. (2013). Australian Dietary Guidelines 2013, p4-24
* National Health and Medical Research Council. (2006). Nutrient Reference Values for Australia and New Zealand Including Recommended Dietary Intakes. NHMRC
* Osteoporosis Australia. (2013). Calcium. Retrieved from http://www.osteoporosis.org.au/
* Wahlqvist, M. L. (2011). Food and nutrition : food and health systems in Australia and New Zealand (3rd Edition ed.). Crows Nest, NSW, Austrlia: Allen and Unwin.