Nutritional needs, is this correct?

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Nutritional needs, is this correct?

Postby JacobHeitmann » Thu May 26, 2016 7:24 am

This is a text about nutritional needs adapted for "us". But is it correct that you would agree upon? I've marked with bold at the important parts. Thanks your all your help and effort helping us out! :-D

"So, the numbers are typically based on USDA rdas. The numbers I tend to recommend (since there is such international discrepancy over Recommended nutrent intakes, and whether they are truly recommended intakes or reference nutrient intakes) are those set by the world health organisation (WHO) in their booklet


The trouble with nutrient intake requirements is that they vary so much depending on different factors.


For example, calcium intake requirements varies depending on consumption of protein, phosphorus, magnesium, sodium as well as due to consumption of anti-nutrient properties such as oxalic acid. Ideally, we want a 1:1:1 ratio between calcium, phosphorus and magnesium. when our sodium intake is less tha 1.15g per day, our calcium requirements drop drastically. When our consumption of animal proteins in the diet reduces our requirements reduce, and when they are completely eliminated they change even more.
Similarly, our zinc requirements vary dramatically, depending on whether we consume anti-nutrients such as oxalates and phytates, as well as whether we are exercising dramatically, taking medications or recreational drugs and whether the food sources are easy to digest.


If you read through the booklet it can be heavy reading if you don't have a science background in parts but fo the most part its pretty approachable I think. But I think its certainly worthwhile as you can start to see all the different recommendations that are actually given depending on the different factors in our diet and lifestyle, and why they make a difference. And you can start to see that the often quoted WHO recommendations are only based on safety margins (assuming you are consuming all the anti-nutrient factors, high protein and sodium intakes etc) so they can account for as many people as possible. So it becomes clearer that for most people, as long as they are not grossly deficient when they come to a raw diet, their nutrient requirements may be much lower than on previous diets consumed.


Most of the figures I tend to recommend are based on figures found in the WHO recommendations. Where a clear recommendation is not available (eg. with vitamin E, which is dependant on PUFA intake), I tend to just recommend what the UK government recommend in their DRV book produced by the DHSS, or what is an average of countries recommendations.


Some of the figures I recommend are similarly based on a margin of safety, and our nutrient requirements may infact be much lower (eg. omega 6), but I think its best to be safe rather than sorry.


It is important to remember that whilst these numbers may be useful for an average person, they cannot apply for everyone. Depending on whether you are severely nutrient deficient already, whether you have poor absorption of nutrients or intestinal damage, whether you live in a city, are pregnant, are male, female, under 18 or over 60, whether you use recreational or medicinal drugs or have done in the past, your nutrient requirements may vary substantially from these figures one way or another.


So, for most figures, I think you don't need to worry about changing, as long as you're getting enough calories (if you arent getting enough, your nutrient requirements will be higher as you will have an increased requirement due to the greater demand by organs like the adrenals and the nervous system.


Numbers I think that can be adjusted include:


Omega 6- You want to be getting at least as much as omega 3 (either 1.1g if youre female or 1.6g if youre male), or perhaps a little higher (2-3.3g)


calcium - as long as you are not consuming any salt (except for natural sodium in veggies and fruit of course) and animal products (be they eggs, dairy, meat or fish) then your calcium requirements are likely to be pretty low, although as mentioned previously, how low will depend on a number of factors. I think we shoudl ideally have a 1:1 ratio with phosphorus and ideally magnesium, but if one has to be higher than the other, I would say it should be calcium. 450-500mg should be sufficient as long as you are getting enough vitamin D.


Zinc - our requirements can be incredibly low if we are not consuming phytates, oxalates and tannins in our diet, and if we are not consuming refined sugars, medications, recreational drugs including caffeine, cigarettes, cacao and alcohol. How low will vary, for some non-pregnant, non-lactating females, this figure may be around 3mg, whilst for males, it may be around 4.3g. Though there is no certainty in this issue, since most variations in requirements are based on whether the diet is high in animal or grain products, rather tha fruit. As such, I tend to say that its wise to make sure one is getting at least 4.3mg, and ideally, 7mg for safety.


Selenium - there is no certainty on this. Some countries have had very low intakes (around 10mcg) with no problems. Certainly, almost all cases of people getting selenium deficient conditions involve those consuming intakes lower than 17mcg. However its generally recommended that the minimum women should aim to consume is 21-26mcg and for males around 26-33mcg as the minimum.


Sodium - Our requirements vary dramatically, depending on activity levels, climate, altitude, potassium intakes, kidney function and other factors. We can adapt to intakes as low as 69mg but its generally recommended to consume around 450-500mg per day.


Vitamin K - The requirement is thought to be 1mcg per kg bodyweight so that means that if you weigh 65kg, you need 65mcg


vitamin E - There's no consensus on our requirements for vitamin E, since our requirements depend upon our intake of PUFA's like omega 3 and 6. Its considered that if you are consuming more than 4.8mg per day then you are probably ok, but its usually recommended to consume 10mg or more per day."

Source: http://www.30bananasaday.com/forum/topi ... t%3A526415
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Re: Nutritional needs, is this correct?

Postby JeffN » Thu May 26, 2016 8:27 am

I appreciate your attempt but I would not say I agree with it, though I think some of it is based on material I have posted in these forums.

First, I don't recommend giving out specific health advice in public anonymous forums, like where you posted it. Those forums are "ripe" with pseudo science, myths and misinformation.

Second, a document like that is giving health advice (though generic) to the general public. With that comes a responsibility. if I was to put something like that out (though the details might be different), I would want it carefully referenced with original primary citations and reports supporting my points and make sure the are being interpreted correctly and I would want to know the qualifications of the person putting it out there.

Third, in a way, it is paradoxical, as it says that our individual needs are so different that you can't say, then you go ahead and say what you say you can't say.

Fourth, you are adjusting it to those on a mostly fruit diet, which I don't recommend.

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Re: Nutritional needs, is this correct?

Postby JacobHeitmann » Thu May 26, 2016 12:57 pm

Thank you for a quick answer!

I do agree with you and working hard to get rid of all of the pseudo science, myths and misinformation I've been taught. Happy to be on the right track for the last ~5 years now, mostly thanks to you and the 'plant based whole food' network keeping it real.

Do you got some material somewhere that focus on these nutrients in detail, like this text did? I've been looking through your FAQ at your section but could only find a very few nutrients that you focus on in detail, like protein, sodium etc. And I'm looking for Information focused on a cooked plant based diet of course, the mostly-fruit honeymoon is over for me, even though I got a lot of fruits at home most of the time. :D

I understand you can't put it out without a large effort behind it all, with all the references and stuff. But it would be nice to learn more about our "special" lower or higher nutrient needs when switching to a plant based diet, even if it's a rough estimate with safety marginals.

Best regards :)
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Re: Nutritional needs, is this correct?

Postby JeffN » Fri May 27, 2016 7:24 am

The best documents are the NAS, IOM, WHO & FAO documents on nutrient needs

http://www.nap.edu/topic/380/food-and-n ... ce-intakes

http://www.nap.edu/search/?topic=380&te ... +reference

http://www.who.int/nutrition/publications/nutrient/en/

http://www.nationalacademies.org/hmd/Ac ... ables.aspx

http://www.fao.org/docrep/004/Y2809E/y2 ... m#Contents

It is also important to understand the differences in RDA, DRI, AI, EAR, etc and how they come to these numbers and what they represent.

For the most part, in trying to give guidance to a population, which is their intent, I think they do a great job and for most nutrients, get it right.

The ones I have comments on are the ones discussed in this forum, which usually refer to the documents above and any changes I think are warranted and why. These include Sodium, Fat, Vitamin E, Zinc, Calcium, Omega 6, etc

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Re: Nutritional needs, is this correct?

Postby JacobHeitmann » Sun May 29, 2016 10:36 am

Thank you! :thumbsup: Going to do some reading now. :)
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