A few months ago I found out that my daughter had an iron deficiency. I was shocked considering how many leafy greens she consumes in a day, not to mention how meticulous I am about making sure that she gets adequate amounts of all the food groups.
Her pediatrician suggested that she could be consuming too much dairy. A light bulb went off right away as I already knew that calcium blocks iron absorption, but I had failed to factor that in when planning her meals. I had not only been giving her too much dairy (she loves cheese and yogurt), but I had been adding it to almost every meal ever since I stopped breastfeeding her several months ago. She wouldn’t drink milk alone and I misguidedly thought that she needed it to replace the breastmilk that she wasn’t getting anymore.
Sooo I started her on an iron supplement and reduced her dairy intake. The doctor asked that I have her iron and hemoglobin levels checked again in about ten days to make sure her body was absorbing the iron. Her hemoglobin levels increased so quickly that her pediatrician said he would have expected to see those results after a month of taking supplements, not after a mere ten days. Clearly the reduced dairy made a huge difference as that was the only change I had made to her diet.
Sometimes nutrient deficiencies are not caused by an inadequate amount of that nutrient in your diet but rather by too much of an anti-nutrient, as in my daughter’s case. Bioavailability refers to how well a nutrient can be absorbed and used by your body. Just because a food contains a high amount of a certain nutrient doesn’t necessarily mean that your body will absorb it, and some nutrients need others in order to be absorbed.
Also bear in mind that the food that we eat today is not as nutrient dense as it was a few decades ago. By breeding and selecting for varieties that give better yield, longer shelf life, disease resistance and more durability during transport, we have lost the nutrient density that the original varieties contained1 in addition to the loss of nutrients from soil depletion. This is why it is important to be mindful of which nutrients work well together and which don’t when planning your meals in order to get the most nutrition possible from your food.
Tips on getting more nutrition out of your food:
1. Iron. Pair your iron-rich foods (red meat, beans, lentils, pork, poultry, seafood, leafy greens, nuts, seeds, fortified cereals, bread and pasta) with some fruit or red peppers to make sure that you get enough Vitamin C to help your body absorb all that iron. Zinc also aids iron absorption. Foods high in zinc include oysters, meat and poultry, beans, nuts, seeds, whole grains, fortified cereals, and seafood.
2. Calcium. Most dairy is fortified with vitamin D to make sure that your body can absorb the calcium, but if you’re vegan or lactose-intolerant, then you should pair your non-dairy calcium-rich foods with some vitamin D to ensure that you are absorbing it. Mushrooms are the only vegan food sources of vitamin D aside from fortified beverages, so a supplement might be a good idea if you don’t get a lot of sun exposure. Inulin is also required for calcium absorption; it can be found in bananas, garlic, leeks, asparagus, onions, and certain herbs.
3. Phytates. Phytate binds to minerals and makes them less bioavailable2. Sprouting grains, beans, nuts and seeds before you eat them will reduce their phytate content, allowing your body to absorb more of the zinc, iron, calcium, and magnesium in those foods2.
4. Vitamins A, D, E, and K. These are the fat soluble vitamins, meaning that they need fat to be absorbed by your body. Pair them with healthy fats like vegetable oils, avocados, and nuts. If you follow a low-fat diet you could be hindering your body’s ability to absorb these vitamins. Healthy fats are an important part of a balanced diet.
5. Avoid caffeine with meals. Caffeine blocks the absorption of many vitamins and minerals, so if you choose to drink coffee or tea, do so in moderation as excessive caffeine intake can lead to nutrient deficiencies.
7. Eat a variety of healthy foods in moderation. You can eat the healthiest foods in the world but too much of anything is never a good thing.
For an example of a recipe that uses the above food pairing rules try my Mango Kiwi Banana Smoothie With Greens and Avocado
References
1. M.J. Stephey. Eating your veggies: not as good for you? TIME, 2009. http://content.time.com/time/health/article/0,8599,1880145,00.html
2. Sandberg, Ann-Sofie; Andlid, Thomas. Phytogenic and microbial phytases in human nutrition. International Journal of Food Science & Technology. Oct2002, Vol. 37 Issue 7, p823-833. 11p. DOI: 10.1046/j.1365-2621.2002.00641.x.
3. World’s Healthiest Foods. http://www.whfoods.com/