Healthy eating habits/Optimising iron intake in a plant based diet

The following page provides a guide on the importance of iron and how individuals following a plant based diet can optimise their iron intake.

Vegetables

Iron basics

edit

What is iron?

edit

Iron is not just a metal, it is an essential mineral vital for many body functions.

The role of iron

edit
 
where 2/3 of the body's iron is stored

1. Oxygen transport- Iron is an important part of a protein found in red blood cells. This protein allows red bloods cells to bind to oxygen. The oxygen in then able to travel through out the body in the blood. This accounts for 2/3 of the iron in the body.

2. Iron is also part of protein found in the muscles. Similar to iron's function in the blood, this protein in allows oxygen to be carried in the muscle where it is used to create energy and allow movement.

3. Iron makes up a part of many enzymes, that have various functions in the body including immune function.

[1]

Haem and non-haem iron

edit

Haem iron or animal iron: This type of iron is contained in animal flesh. Haem iron is absorbed 50% better than Non-Heam iron.

Non-Haem iron: This iron is found in both animal and plant based foods.

Non-haem iron is the only type of iron that vegetarians consume. For this reason it is important that those following a plant based diet are careful to ensure they are consuming enough iron.[2]

Iron requirements

edit

The Recommended Daily Intakes, as suggested by the Australian Health and Medical Research Council, for iron are as follows:

Men: 8mg

Women: 18mg [3]

Iron deficiency

edit

Anemia

edit

If iron stores are low over a long period of time this may lead to a condition know as iron deficiency anemia. Anemia is a condition in which the body red blood cell count becomes deficient. Lack of red blood cells means that the blood cannot carry enough oxygen around the body.

Symptoms

edit
  • Symptoms of iron deficiency :
  • Brittle nails
  • Soreness and swelling of the tongue
  • Cracks on the side of the mouth
  • Restless leg syndrome

Symptoms of anemia (long term iron deficiency):

  • Tiredness
  • Pale skin
  • Dizziness
  • Weakness
  • Breathlessness
  • Headaches
  • Cold hands and feet
  • Chest pain
  • Reduced immune function

Can you have too much iron?

edit

Yes, too much iron in the body can be toxic, the name of the condition characterised by excessive iron stores is haemochromatosis. In the long term haemochromatosis can cause failure of the organs such as the liver, pancreas and the heart. The maximum safe level of intake for adults is 45mg a day.

[4].

Food sources of iron

edit

Many vegetarian foods are good sources of iron, this includes pulses, legumes, dark leafy green vegetables, grain, cereals and dried fruits.

 
Bok Choy
 
Yellow lentils
 
Raw spinach
 
Raw tempeh (fermented soy)
The amount of iron found in some vegetarian foods
Iron rich foods Serve size Amount of iron (mg)
Black beans 1 cup 3.4
Cannellini beans 1 cup 4.1
Bok choy 1 bunch 3.2
Chickpeas 1 cup 3.3
Corn flakes 45g 4.5
Sultana bran 45g 6.1
Rice bubbles 45g 7.0
Dried apricots 5 1.5
Lentils 1 cup 3.8
Milo 1 tablespoon 6.0
Cashews 30g 1.9
Peas 1 cup 1.7
Quinoa 1 cup cooked 2.8
Brown rice 1 cup cooked 2.2
Rye bread 1 slice 1.0
Raw spinach 1 cup 1.6
Tofu 1/2 cup 3.6
Tempeh 1/2 cup 7.4
Marmite spread 1 teaspoon 3.2

All data from NUTTAB 2010 [5].

Factors influencing iron absorption

edit
Factors enhancing iron absorption
 
Orange juice containing Vitamin C
There are a variety of factors than may enhance the absorption of non-haem iron, including:

Vitamin C
Which is found in foods such as oranges, lemons, limes, berries, tomatoes and kiwifruits

Sugar
While it is not recommend to consume excess sugars in the diet, natural sugars, such as honey, may assist iron absorption. [1]

Factors inhibiting iron absorption
 
A cup of coffee containing caffeine

There are a variety of factors than may inhibit the absorption of non-haem iron, including:

Caffeine
Caffeine, when consumed 1 hour before or after high iron foods may inhibit its absorption.
Foods containing caffeine include tea, coffee, energy drinks (like redbull, V and mother) and chocolate.

Calcium
While calcium is a mineral that is important for many bodily functions, including bone health, when consumed with iron rich foods it may block its absorption.
Calcium is most commonly found in dairy foods such as milk, yoghurt and cheese. [1]

Example of a high iron meal plan

edit

Example 1

edit
Iron(mg)
Breakfast 2 Rye toast with 2tsp marmite 8.5
Snack 1 Handful of almonds 1.9
Lunch 2 Quinoa, kidney bean & broccoli burrito with guacamole 6.8
Dinner Chickpea, tomato & spinach curry with brown rice 7.1
Total 24.3

Example 2

edit
Iron(mg)
Breakfast Banana oatmeal with pumpkin seeds and dates 5.9
Snack 1 Cup of milo made with water or soy milk 6.0
Lunch Tempeh & avocado sandwich 9.4
Dinner Black bean chili with veggies & tofu 7.0
Total 28.3

Further information

edit

Additional information can be found at:

Nutrient reference values

Better health

Anemia facts sheet

The Vegetarian Resource group

Dietetics Association of Australia

References

edit
  1. a b c Better health channel. (2014). Iron. Retrieved from http://betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Iron_explained
  2. National Institutes of Health. (2014). Supplement fact sheets. Iron. Retrieved from http://ods.od.nih.gov/factsheets/Iron-HealthProfessional/
  3. NHMRC. (2013). Nutrient Reference Values.Iron. Retrieved from http://www.nrv.gov.au/nutrients/iron
  4. National Heart, Lung and Blood Institute. (2014). Iron-Deficiency Anemia. Retrieved from http://www.nhlbi.nih.gov/health/health-topics/topics/ida/signs.html
  5. Food Standards Australia and New Zealand. (2010). NUTTAB. Searchable database. Retrieved from http://www.foodstandards.gov.au/science/monitoringnutrients/nutrientables/nuttab/Pages/default.aspx