Bioavailability or absorption % of supplements

VegasTortoise

Question: When adding supplements, does Cronometer take into account average absorption or is the whole amount of supplement added to the nutrition profile? Also does the software distinguish between absorption of, say, calcium carbonate and calcium citrate?

Karen_Cronometer

Hi VegasTortoise,

Absorption of nutrients in a mixed diet is generally used when experts create the dietary reference intakes (DRIs). In other words, the nutrient targets are set higher to account for the fact that not all of a particular nutrient that is in your food is absorbed. This is more of an average absorption approach.

Unfortunately, we don't have the level of detail in nutrition research to know each individual's needs and absorption rates from different sources (yet!), so the nutrient targets are based on what the average healthy omnivorous person gets in their diet then adds a factor to make sure most of the population will meet their needs by consuming 100% of the target for your age, sex and lifestage.

Best,

VegasTortoise

Thank you Karen!

Andromedus

I'm a little confused by this answer. Does it imply that if someone were following a vegan diet, they would have a different DRI, for, say, iron?

Karen_Cronometer

Yes Andromedus! Because the DRIs are based on a mixed diet you may have different requirements when eating a vegan diet. @Susan_RD_101 touches on that here: https://forums.cronometer.com/discussion/comment/14353#Comment_14353

Susan_RD_101

@Andromedus

When it comes to the DRIs, there are various "special populations" that are mentioned under each nutrient. In the case of iron, because it is consumed as non-heme, needs may be as much as 80% higher on a plant-based diet.

Other nutrients that may need to be increased on a plant-based diet include: zinc (by ~50%) and protein (by ~10%). Calcium needs may actually be lower because of the alkalinity of a plant-based diet.

Kind regards,

Andromedus

Thank you for that. Most helpful! So, if eating all vegan, my iron target should be 180%?

Susan_RD_101

@Andromedus

I'd say iron target could be up to 180%. The only way to really know is to have bloodwork done.

If you're an athlete (especially a runner) and a menstruating female, iron needs will likely be this high (if not higher). Vegan men rarely have issues with iron since they aren't routinely losing it from their bodies (unless they donate blood or run).

Hope this helps!

thistle_dave

Great to see this question was answered years ago. There will never be one size fits all, there is a "standard" absorption rate, a what supplements are you taking at the same time (some of them block absorption of the other). Still when someone is reading their nutrition report they should take in consideration the natural sources versus the supplement source for that particular item. I came here because I take B12 supp but only a couple of times a week. Apparently the "standard" absorption is really low thus you are not greatly exceeding the daily target.