Is it a myth or is there something to the proverb?
Tooth loss is believed to be associated with the loss of calcium in your body storage during the time you are nursing your baby. Calcium benefits your bones as well as teeth.
Before considering the effects of lactation on calcium storage let’s look at how calcium stores are build and used in our body. “Calcium aids in muscle contraction, which provides movement and allows for muscle building, blood clotting, which prevents excessive bleeding, and maintenance of cell membranes, protecting individual cells from invasions” (1). Calcium is stored in our bones but needs Vitamin D as well as Magnesium and Boron among other trace minerals to be absorbed (2). Phosphorus, which is found in Cola products, contributes to the loss of calcium from the bones and reduces the calcium absorption from the intestines (2). Caffeine, tobacco and alcohol have also shown to have negative effects on calcium storage (2). Calcium is in particular important for children and teenagers because it aids in the rapid bone growth as it builds healthy bones. The calcium requirements change depending on age (1). While toddlers need between 500 and 800 mg a day, school-aged children need the higher end of that (800mg) a day. During puberty it goes up to 1200 mg a day (1). Once the body is fully grown the calcium requirements go down (1).
Here is an important fact about calcium storage. Between age 30 and 35 your body stops storing calcium in your bones. So the amount of calcium you take in until then will directly effect your bone health at an older age (1,2). However, until age 50 your body is able to not loose the calcium storage. An adult should take between 1000-1500 mg of calcium in addition to Vitamin D 400 IU every day. Milk products are a great source of calcium including non-dairy products such as soy milk, almond milk etc. Other sources are green leafy vegetables, shrimp, salmon, clams, legumes, tofu and as a last resort fortified products such as cereal and orange juice (1). Besides diet and exercise, weight lifting also has a positive effect on making our bones stronger. As you exercise the stress on your bones actually causes bone building (2). “Exercise and weight lifting have also been shown to make bones stronger. Bones are always in a state of balance between building bone and tearing it down. With exercise, stress applied to the bone causes more bone building” (2).
Pregnancy and calcium as well as nursing and calcium adds another dimension to the equation. One of the most fascinating things I have found is that your body gives you about 6 - 12 months from the time you stop nursing to build up your body’s calcium storage that you may have lost during nursing. So, especially once you are finished nursing it is important to give your body nutrients rich in calcium.
The calcium need of the developing fetus is relatively low during the first 2 trimesters of pregnancy. During the early stages of pregnancy the mother absorbs calcium better, as it almost doubles, even though the fetus does not take in an excessive amount at this point (3). Midst the third trimester the fetus requires about 200 to 250 mg/day calcium to help develop a healthy skeleton (3).
Once nursing your infant during the first 6 months your breast milk will provide two to three times the amount of calcium that you provided to your fetus during pregnancy (3). The strain on the mothers bone calcium storage is increased as most of the calcium present in breast milk comes from the mother’s skeleton (3). During the time of lactation the mother’s bone mass density (BMD) can deteriorate by 5 to 10 % during the first 6 month of exclusive breastfeeding (3). But this is where our human body does amazing things, as the calcium stores return back to your baseline during the first 6 to 12 months once you stop breast feeding (3). Thus, in the long run, the amount of calcium you loose in your stores while nursing (even for consecutive babies) does not seem to negatively impact your BMD or put you at risk for osteoporosis (3). Something not to forget is that later in life (>50 years of age), menopause and age-related bone loss will eat away your calcium stores (3).
Bottom line is that calcium in your diet is most important during your 3rd trimester as well as during and post the lactation period. You may not loose a tooth over it but providing your body with calcium in particular during these crucial times may prevent you from developing osteroperosis later on in life. Our body is made to have children and especially with the knowledge we have today, we don’t have to risk our health (or teeth) to give a baby the best nutrition. Even if you are not pregnant or nursing it is not a bad idea to give your body calcium and Vitamin D (best in form of foods and not supplements) as well as physical exercise.
References
1. Calcium. Vitamins and Minerals. BHia.org. http://www.bhia.org/articles/vitamins-and-minerals/calcium.html. Accessed January 19th, 2015.
2. Lindberg. Bone Health: Slow, stop, and even reverse bone loss. Nutrition Express. http://www.nutritionexpress.com/showarticle.aspx?articleid=96Nut express. Accessed January 19th, 2015.
3. Heringhausen J, Montgomery KS. Continuing Education Module—Maternal Calcium Intake and Metabolism During Pregnancy and Lactation. The Journal of Perinatal Education 2005;14(1):52-57. doi:10.1624/105812405X23621. Accessed January 19th, 2015.