Wednesday, December 02, 2009

Liver; can you over do it?

Yes, but you have to be very unlucky!

Olga posted these links on the liver and bacon post out of personal experience but as they won't get seen there, here they are again.

Vit A toxicity 1

Vit A toxicity 2

Vit A toxicity 3

To reiterate, you have to be very, very, very unlucky to become ill from eating reasonable amounts of liver, but it does appear to be possible... For the rest of the world, outside of this small number people with specific vitamin A intolerance, enjoy liver. Bacon and onions are a great accompaniment!

Just for everyone's information.

Peter

10 comments:

jean said...

http://harvestinghealth.blogspot.com/2009/12/more-evidence-of-widespread-vitamin.html

NEWCASTLE, England, Nov. 23 (UPI) -- Half of British women lack vitamin A due to a genetic variation, scientists found.

Researchers at Newcastle University in England, led by Dr. Georg Lietz, found 47 percent of volunteer group of 62 women carried a genetic variation that prevented their bodies from effectively converting beta-carotene into vitamin A.

The findings suggest beta carotene may not be an effective substitute for vitamin A for women whose bodies are not able to make the conversion, Lietz said. Beta carotene has been suggested for pregnant women since a 1987 study linked too much vitamin A with certain birth defects.

"Worryingly, younger women are at particular risk," Lietz said in a statement. "The older generations tend to eat more eggs, milk and liver which are naturally rich in vitamin A, whereas the health-conscious youngsters on low-fat diets are relying heavily on the beta-carotene form of the nutrient."

The study findings were published in the Federation of American Societies for Experimental Biology Journal and were presented at the Hohenheim Nutrition Conference in Stuttgart, Germany.

Eat your liver.

arnoud said...

Mmmm... excessive levels of Vitamin A is toxic, and can even be fatal (rare).....
....inadequate Vitamin A (formed or pre-formed) causes misery...

What is one to do to ensure optimal intake? For Vitamin D, there is the 25(OH) blood serum test. How do we get smart about Vitamin A dosing? Should we take tests, or are there other ways to ensure optimal intake?

Then there is Vitamin A and D interaction. When I started to take CLO regularly, my Vitamin D level dropped significantly (indicating the addition of Vitamin A caused my cells to use more Vitamin D.

Is there a wide or narrow range for optimal vitamin A?

I'll stay with regular liver and/or CLO, but it is time to dig in to some research....

Adolfo David said...

My main problem with liver is that it's rich in inflammatory arachidonic acid. So I never take liver.

Gyan said...

What is being meant by "effective" here
re: effective conversion of beta-carotene to Vit A?

Peter said...

jean, I eat my liver. Uh oh, that sounds like something from Catch 22. I eat lambs' liver mostly!

arnoud, if you are remotely normal then occasional liver is a perfectly reasonable approach to vitamin A. You can store it and use it as you need. Vitamin D is VERY complex and a simple 25(OH)D does not seem to give you all of the answers! Vieth has a new review article out I'm working through at the moment.

Adolfo, I would view this differently. Liver contains lots of arachidonic acid. Arachidonic acid is a neutral raw material. If you wish to mix alcohol with fructose and corn oil you will activate NF-kappaB, generate lots of COX2 and make lots of pro inflammatory eicosanoids out of AA. Leave NF-kappaB alone and AA just remains a cell membrane component. It is possible to convert it to anti inflammatory eicosanoids during the later stages of healing. The "decision" is yours as to what you do with it. Better not to shoot the messenger.

Gyan, I'm boringly normal, along with most of the rest of the world, so I have no issues with liver and eat it as a superfood. The beta carotene conversion I would dig deeply in to if I was vegan. There are reasonable amounts of A in eggs, so even for vegetarians I doubt there is much of an issue...

Actually, going back to jean's post, maybe there is an issue. It's still not something I've followed, being a liver eater myself...

Peter

LPaForLife said...

But what about the high copper content in liver and it's association with cognitive decline?

http://archneur.ama-assn.org/cgi/content/full/63/8/1085?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=copper+cognitive+decline&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT

Anne said...

I really enjoy chicken livers - from organically reared chickens (Waitrose sell organic chicken livers). I'm wondering how much vitamin D is in them ?

J said...

Let me suggest a crude way to put a maximum number on liver consumption. In humans, liver is 2% of the body by weight. Set liver consumption at a maximum of 2% of food intake.

blogblog said...

Eating up to 0.5kg of liver a week should be perfectly safe for most people.

meenu said...

A great blog and lovely tips about ….yummy recipes man!! I stumbled upon this site jus a few mins back…and would love to hang around here for quite some time…nice da!!

Pretty good, pretty good.
Thank you for your time it has meant a great deal......:)

Regards,
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Children’s Vitamins