This topic is not, as my colleague Dr. Cipriano would put it, “sexy.” But, after some consideration I decided to comment on it for the full story.
Phosphorus is located on the periodic table of the elements at atomic number 15, sitting nicely between sulfur and silicon, below oxygen and above arsenic. If you want to know more, check out Wikipedia (and make sure you drop them a donation of a few bucks as well—they certainly deserve it).
In our bodies, phosphorus is a critical component of our DNA, RNA, our cell membrane as well as my favorite organelle, the mitochondria. As such, we need it for survival. Phosphorus is pretty common in our foods and so deficiencies are not common. The most well-known concern with phosphorus is in chronic kidney disease, where the kidneys lose the ability to get rid of excess phosphorus in the urine and phosphorus levels in the body rise.
Elevated phosphorus has to go somewhere, and it has a tendency to land in the blood vessels and contribute to plaquing in the arteries. This is the main reason that people with chronic kidney disease are so susceptible to heart disease.
But there is a darker side to phosphorus. Certain foods, like soda and processed foods, are also high in phosphorus. In sodas, phosphoric acid is the culprit, used to give the drink its characteristic tartness. There is concern that high intake of sodas are increasing phosphorus levels high enough to contribute to heart disease in those of us without kidney failure.
Further, another consequence of elevated phosphorus is that it will affect the conversion of vitamin D into its active form. One of the triggers for your body to activate vitamin D into the active form is a phosphorus or calcium deficiency. This turns on vitamin D, allowing the body to absorb more of these two nutrients.
In reverse, with high blood levels of phosphorus (or calcium) vitamin D does not get activated. When vitamin D doesn’t get activated, we don’t get the REAL benefits of vitamin D on cancer prevention, heart disease prevention, immune protection, vascular benefits, respiratory benefits and more.
All of this leads us to this particular study. In it, researchers looked at the risk of death (all-cause mortality, or the risk of dying from anything) in relation to the levels of phosphorus in the diet. Here’s what they found:
- Individuals who consumed more phosphorus-dense diets were older, were less often African American, and led healthier lifestyles (smoking, physical activity, and Healthy Eating Index).
- In those who consumed >1400 mg/d had a 223% higher risk of dying.
- At <1400 mg/d, there was no association.
- When taken in the context of calories, those taking in more than 0.35 mg/kcal also had a 227% higher risk of dying.
A few comments.
First, it is recommended that daily consumption of phosphorus stay around 1,000 mg for most age groups. As mentioned, processed foods and sodas have increased the phosphorus intake of Americans in recent years, and this may largely contribute to the problems seen with elevated phosphorus.
The only thing that throws a wrench in the works of this thought process is the note that those with healthier lifestyles had higher phosphorus intakes. This is obviously a wee bit disturbing, made even more so by the fact that, without looking much deeper into the study, I really don’t have any idea how the link between healthier diets and high phosphorus diets plays out.
It is, however, very common for some people to eat what they consider “healthy” foods that really are not. Some of these foods may be high in phosphorus content like prepared frozen foods, dairy products (like yogurt and milk) and breads (leavening agents). It is entirely possible that, when looking at the “healthy” foods in more detail that we would see that these foods are high in phosphorus.
In the meantime, this study just gives us even more reasons to avoid soda and processed foods in our diets.