What do common breakfast foods like cereal, granola, and toast all have in common? They’re all fortified with folic acid. Which would be great, except that on top of a healthy, balanced diet (and multivitamin, which typically contain 100% daily value on their own), all those fortified foods may lead to excess folic acid intake, something that could fuel pre-cancerous cell growth.
Over a decade ago, the government began enforcing mandatory fortification of enriched grains, like white flour and rice, with folic acid (the synthetic form of the B vitamin folate) in an effort to reduce birth defects. (Folate consumption during pregnancy benefits neurological development in the fetus; deficiency can cause serious problems, like the neural tube defect spina bifida, in infants.) Now, food manufacturers pump folic acid into everything from breakfast cereals to energy bars and even beverages, which has gone a long way towards producing healthy babies. In fact, since 1998, the number of these birth defects dropped by about 19 percent. But new research suggests that there might be hidden side effects for the rest of us.
For pregnant women, the RDI is about 400-600 micrograms, which can be achieved through healthy diet and prenatal supplements. But for men and women of non-child bearing age, excess folic acid left unmetabolized in the body may impose serious cancer risks.
A study at Tufts School School of Medicine shows an increase in the rates of colon cancer in the late 1990′s around the same time fortification arose in the US. In other countries, such as Norway, fortification is not required and a study showed that daily supplementation with 800 mcg of folic acid (plus B6 and B12) for more than 3 years raised the risk of developing lung cancer by 21%. Furthermore, studies reveal prostate cancer risk is twice as high in men who consume 1,000 mcg of folic acid daily. Half of adults older than 60 could already have precancerous colon polyps, while most middle-aged men have precancerous cells in their prostates. Excess folic acid circulating in our bloodstream may fuel the fire for precancerous cells that already exist in the body.
The key to solving the folic acid paradox is to understand how much folic acid we are consuming from our diet and to rethink our supplementation. Here’s a sample breakdown of the folic acid intake for one day’s worth of meals:
Breakfast: 1 cup Cheerios with skim milk, 1 cup orange juice. Contains about 200 mcg folic acid.
Lunch: Turkey & Swiss Sandwich, handful of pretzels. Contains about 200 mcg folic acid.
Dinner: Teriyaki chicken & vegetables with 1 cup steamed rice. About 100 mcg folic acid.
Total Folic Acid Intake: Approximately 500 mcg.
If you’re eating adequate grains, legumes and plant-based foods, you’re most likely consuming adequate folic acid in your diet. For most of us, the folic acid from a multivitamin is unnecessary, and may even be harmful. A typical multivitamin contains about 100% of your daily value of folic acid (or 400 mcg). You could potentially be consuming about 800-1000 mcg of folic acid daily between fortification and supplementation and not even realize it! Prolonged excess of folic acid in our bodies is what increases risk for cancer. To keep precancerous cells at bay, evaluate your folic acid intake and stay in a safe range.
If you’re worried that you won’t be getting adequate nutrition without your supplements, switch your focus to obtaining vitamins and minerals from whole foods. Here are some tips that may potentially save your life: