What is AlgaeCal?

Question

Have you ever heard of AlgaeCal? I'm being deluged with ads saying any nutrient supplied in natural form such as from plants is better absorbed than nutrients supplied from rocks.

Answer

AlgaeCal is a calcium supplement produced by AlgaeCal Inc. that is made from red algae. AlgaeCal claims that their supplements slow bone loss, increase bone density, and are easily digestible. They say that because the algae plant draws calcium and minerals from seawater, the calcium is “pre-digested” and is more bio-accessible and “bone cell friendly.”

There are two main forms of calcium supplements available: calcium carbonate and calcium citrate. These supplements are either synthetic (created in a lab) or come from rocks such as limestone. These supplements dissolve when they come in contact with your stomach acid and the calcium can be absorbed into your body. AlgaeCal claims that because their product is derived from plants it increases the degree to which the calcium is absorbed into the body (the bioavailability of the calcium). However, calcium derived from algae is still just calcium carbonate, and it is not a new calcium supplement form.

AlgaeCal posted four studies touting the effectiveness of their products on their website. While all of these studies reported positive findings, none of them present compelling evidence that AlgaeCal is significantly more effective at improving bone health than other calcium supplements. The NWHN is also concerned about the study designs. Some of these studies are observational, and therefore cause and effect cannot be determined. Others were tests done on bone cells (osteoblasts) or in mice, and therefore may not apply to clinical studies. Physical activity, which is known to improve bone health, was also included in one of the studies as part of the treatment regimen. Therefore, further analysis would be required in order to determine whether bone density was affected by the AlgaeCal supplements, the activity, or the combination of the two. Furthermore, one of the studies measured bone mineral density after treating two groups with differing doses of AlgaeCal, yet the treatment regimen also included their Strontium Boost product. Strontium is similar to calcium and is thought to improve bone density. A prescription form of strontium ranelate to treat osteoporosis is available in Europe but it has not been approved by the FDA. Strontium supplements (not the same as ranelate) are available over the counter in the U.S., but there have been no studies that show they are safe or effective. Taking strontium supplements can actually lead to inaccurate bone density tests later in life. All of these factors potentially skewed results thereby making it difficult to draw any significant conclusion from these studies.

There is also a study from 2012 not included on the AlgaeCal website that looks at the difference in bioavailability between AlgaeCal and Caltrate600 but no results have been posted yet. Currently, there is no compelling clinical evidence to support AlgaeCal’s claims.

Additionally, the studies of the effectiveness of AlgaeCal compared it to calcium carbonate and to calcium citrate alone. It did not compare its effectiveness to common supplements available that have a combination of other minerals as well, such as magnesium, zinc, and vitamin D3. These minerals are known to increase the bioavailability of calcium, and it may be the presence of these vitamins and minerals in the AlgaeCal that increase its effectiveness. Therefore, the increased bioavailability of calcium would not be a unique feature of AlgaeCal, and AlgaeCal would not be more effective than these common, less expensive alternatives.

The NWHN believes that additional clinical studies are needed to prove that AlgaeCal and calcium from red algae is significantly better than other available calcium supplements. Given the evidence that is provided, as well as further research on the effectiveness of red algae for calcium, it is possible that AlgaeCal is, in fact, effective. However, there is not enough evidence to justify the higher cost of AlgaeCal, and more research must be done. As of now, AlgaeCal is safe for consumption but is not significantly better than the less expensive, over the counter calcium supplements currently available.


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