all the nutrients

fipzzz

as a vegetarian it wasnt that simple to find a good combination of foods that give me all i need while not overdoing it on very common nutrients like manganese and copper. so now i am really proud of my work, every nutrient slightly above 100%. but did i make a mistake and didnt consider that i wont absorb most of it? or do the numbers already take this into account? i was so proud haha please can anyone confirm or disprove my worries?

LLJames

Hello, this is a forum user, LLJames.

What do you mean by overdoing it with manganese and copper? You can never absorb too much manganese and copper from food. That's impossible.

As far as absorption, your body simply absorbs what its going to absorb based on many complicated factors. There is no rule or fixed absorption rate in any human body. It takes what it needs and either stores or excretes the rest. There is no general rule for what the body absorbs.

Just keep your food choices well rounded and meet your nutritional goals as best you can. Some days, you may get less protein and in others more. Some days more vitamin C and in others less. Your body already knows what to do if you're eating healthy food choices.

Here is an article to help you get a quick understanding of food absorption. http://www.quickanddirtytips.com/health-fitness/healthy-eating/know-your-nutrients/how-much-nutrition-do-you-absorb-from-food

fipzzz

thank you for the quick response. i remember hearing that one should not eat too many brazil nuts as they contain too much selenium, which can become toxic at those heights. i also remember that vegetarians have the adventage with vitamin a because beta carotene the body can rule over how much gets converted into actual A while non-vegetarians get the full load. there were other cautions as well, and from there i concluded to better watch more carefully whats in the food. however, im going to read the article and we will see if its enlightening

LLJames

You're very welcome. Definitely read the article.

Brazil nuts are so oily and rich, that the flavor gives me an indication to stop eating them. Once I've eaten about 5 of them, I feel like I've eaten one too many. So, they're not an every day food for me. Around 2 or 3 are crushed as a garnish once in a while over a specific meal. Otherwise, its not a staple food, so I'm not in any danger of overdosing on selenium.

As far as vitamin A, it comes in the form of beta-carotene in plants. Your body converts it into vitamin A as needed. Vitamin A comes in another form is in meat. The only known reported case of overdosing with vitamin A is the synthetic version that comes in a bottle in vitamin form.

LLJames

Susan_RD_101

@LLJames - Great answer! I'm an RD and consultant here at CRON-O-Meter and I couldn't have said it better myself. @fipzzz - there are very few nutrients that you can overdo with food. However, selenium is one of them. At daily high doses, selenium can cause symptoms such as hair loss and nail brittleness. Limit your daily intake of Brazil nuts to a maximum of 5. (Although, all you need is one Brazil nut to meet 100% of your selenium requirement. )

HankG

Good points above. One of the powerful things about this site over others is the amino-acids break down too. I love the fact that one can do a vegan diet and know that they are getting sufficient amounts of all amino acids. It's not that hard to do if you are eating a diverse whole foods plant based diet.

I don't think your original question was answered. I believe you are asking about if the bioavaliability of the micronutrients is taken into account in the numbers. The big micronutrient that comes to mind with that is Calcium. I found this article which provided a table of bioavailibilty of Calcium. I honestly don't know the answer about if the numbers in the databases are for bioavailable levels or the original levels. I hope one of the RD's can enlighten us.

https://plenteousveg.com/vegan-sources-calcium/#calcium-bioavailability

Susan_RD_101

@HankG

Thanks for your comment! Off the top of my head, I believe that there are a few nutrients where the Dietary Reference Intakes mention changing requirements based on bioavailability (such as the increased iron needs on a plant-based diet or for those who are very physically active). However, I don't believe this actually translates into number recommendations.

In general, nutrient recommendations have been established from those who eat a mixed diet so anyone not eating this way may require more or less of a specific nutrient, based on the components in his or her diet. Unfortunately, it's difficult to know exactly what that amount is.

Calcium is a good example to show how the bioavailability is actually better in some plants when compared to cow's milk, but the amount you get per serving is less overall.

Hope this answers your question!

HankG

@Susan_RD_101 I think we are talking about two different things, but I admit the topic is confusing. I was more talking about the nutrient values of specific foods. For example, according to the CRON-o-meter database 1 ounce of raw kale has 161.1 mg of Calcium, about 16% of RDA based on 1000 mg a day. According to one source I found kale's calcium absorption rate is about 50%. So does that 161 mg already factor in the absorbability or does it only reflect the raw value and the user needs to be aware that they only got half of the Calcium they thought they did?

Susan_RD_101

@HankG

Thanks for following-up! I understand your question now and did it ever take me down a rabbit hole! In general, I don't believe that most databases account for the total bioavailability of calcium (although some factors may have been considered). Thus, it would be up to the individual to keep in mind the varying bioavailability of different foods.

Using your example above, 161 mg of calcium from kale would provide ~ 80.5 mg of absorbed calcium to the body). In general, we want to absorb a total of 250 mg of calcium per day. This gets pretty complicated and I would never expect anyone to engage in such an experiment.

I do know that it has been theorized that vegans not have as high as calcium needs due to the akalinity of their diet and the fact that there is better absorption of the calcium foods they are including. However, I haven't seen any solid research to back this up.

Please let me know if I'm still missing the mark on your question!

HankG

@Susan_RD_101, yes that nails it! Thanks! Appreciate the insight on how much we need to absorb as well.

Susan_RD_101

@HankG

Glad I was able to help! Enjoy your day!