I have been reading several articles on classification of nutrients as type 1 and type 2 based on how the body responds to their deficiencies. I am confused that all vitamins are considered type 1 nutrients which, under this classification, do not affect growth. Well we know that vitamin A regulates cell differentiation and thus growth. So, even if all type 2 nutrients were adequate, a deficiency in vitamin A should still be affecting growth. Also, it is not clear to me if this classification is taking into account nutrient-nutrient interactions. e.g. Zinc a type 2 nutrient interacts with Vitamin A. Thanks
From Craig: It's true that ultimately Vitamin deficiency will affect growth but the primary sign of deficiency is not reduced growth but maybe night blindness ( Vitamin A). That's my own understanding.
Tamsin Walters
Forum Moderator

Answered:

9 years ago
Vitamin A deficits will manifest themselves quite early with "eye signs" (night blindness, Bitot spots, and the like). These are early and specific signs of VA efficiency. Increase susceptibility to infection and increase duration of symptoms associated with VA deficiency will probably affect growth earlier and more profoundly than VA deficiency alone (i.e. in the absence of infection). I believe that Mike Golden originated the type 1 / type 2 nutrient model. He often responds on this forum. Perhaps EN-NET staff will prompt him.
Mark Myatt
Technical Expert

Answered:

9 years ago
Thanks for replying. I was also thinking that the term/wording "the body's initial response to a nutrient(s) deficiency" would perhaps be more appropriate to use in this case. Thanks and regards
Yasmin

Answered:

9 years ago

In fact, Dr Mel Sydney-Smith, Brisbane, has been teaching integrative medicine for over 30 years, and quotes from The Oxford Textbook of Medicine on the differences between Type 1 and 2 nutrient deficiency. With the latter, all the items need to be provided in the correct amount and ratio, otherwise the body actually shrinks and the patient develops symptoms of anorexia, fatigue and cognitive difficulties.

Dr Ashley Berry

Answered:

6 years ago

These classifications may be somewhat helpful, but deficiencies are not as clearcut as typing makes them sound. There are crossovers and physiological interactions that frustrate classification. Zinc deficiency is one. There are physical signs of zinc deficiency in the form of alopecia, dermatitis, diarrhea, night blindness that may appear before anthropometrics demostrate growth delay.

Laurie Sauerwein

Answered:

6 years ago

“ PIP: A child responds to a deficiency of an essential nutrient either by continuing to grow and consuming body stores with eventual reduction in the bodily functions (Type I) or by reducing growth and avidly conserving the nutrient to maintain the concentration of the nutrient in the tissues (Type II). Examples of Type I nutrient deficiency are anemia (iron deficiency), beri-beri (thiamin deficiency), pellagra (niacin or nicotinic acid deficiency), scurvy (vitamin C or ascorbic acid deficiency), xerophthalmia (vitamin A or retinol deficiency) and iodine deficiency disorders. Diagnosis is relatively simple via clinical symptoms and measurement of the concentration of the nutrient itself. There are no characteristic symptoms to distinguish which Type II nutrient deficiency an individual has; all deficiencies result in the poor growth, stunting, and wasting generally ascribed to protein-energy malnutrition. In Type II, growth stops, the body starts to conserve the nutrient, and its excretion falls to very low levels. In severe deficiency the body may start to break down its own tissues and the reduction of appetite accompanies this condition. An animal can die from zinc deficiency even though it is has a normal concentration of zinc in its tissues, but it can respond rapidly to small amount of dietary zinc. The mechanisms by which the body stops growing in response to nutritional lack are similar to the hormonal picture seen in endocrine disease (reduction of the production of the hormonal mediators of growth, down-regulation of receptors, and reduction of protein synthesis). Growth failure is the clinical sign characteristic of a diet deficient in protein, zinc, magnesium, phosphorus, and potassium. Wasting may be also ascribed to toxins, infection, worms, or persistent diarrhea. Anorexia is another common response in nutrient deficiency. Only a supplementation diet with a balance of nutrients will promote rapid recovery”.

This is from Pubmed; truly i just learned it well! 

Dr Hana Fayyad.

Hana Fayyad

Answered:

4 years ago
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