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Ratio risks in nutrition

Unless ratio measurements are reported with the underlying risks , readers of nutrition and clinical reports cannot cannot judge the significance of the effect.
Nutrition is not renowned for giving such data and this is a real deficiency as strong claims are made for the adverse or positive benefit of the nutrient or food being studied and yet the data is very subjective to the authors whim. The failure to give such figures may well exaggerate a claim.
It is necessary for nutrition to be more rigorous in defining risk

see

Ratio measures in leading medical journals : structured review of accessibility of underlying absolute risks. Schwartz et al BMJ 2006, 333, 1248-50

Management of severe malnutrition in children

Severe acute malnutrition is defined as a weight for height measurement which is 70% less than the median, bilateral nutritional oedema, mid upper arm circumfrence of less than 110 mm in children aged 1 to 5 years old (possibly the best and easiest measure) .
Chronic malnutrtion is defined by a height for age ration ie stunting.
Both contribute to the death of 10 million children under the age of 5 years each year. 60 million children in the world have moderate acute malnutrition 13 million with severe. 3-15% of these children will die. This problem is complicated by infection and diarrhoea
The mortality in such situations is high even in hospital 25%.
The causes are poverty, social exclusion, poor public health and in general requires economic development for all and improved public health.
As acute malnutrition deteriorates, there are adaptive processes in the body( reductive adaptations ) drawing on energy and nutrient reserves and reducing energy and nutrient demands. These however affect the bodies ability to withstand infection, eg tuberculosis and AIDs
The centres treating these children are in poor parts of the world with limited facilities.
Treatment is best on an in patient regime, in a well trained environment using WHO protocols. Realistically community care must be the end goal .
The basisi is stabililisation and rehabilitation.
The use of ready to use therapeutic food with a sufficiency of nutrients, vitamins and trace elements is so important but not always available. Oil based pastes have advantages as infection of the food which can happen with water based fods is minimised.Such treatments help move care from hospitals into the community.
Collins et al Review, Management of severe acute malnutrition in children Lancet.2006, 368, 1992-2000

Love of all things antioxidant.

love of all things antioxidant.
While it is difficult to be against antioxidants, I have to say I am not impressed. Oxidation is a normal end-product of metabolism and is required to kill bacteria and, probably tumor cells, within white blood cells. So if you’re not worried about infections or cancer, antioxidants are pretty good. I feel the anti-oxidant story is hugely speculative. Think of all the care and attention goes into clinical trials to develop the efficacy of drugs and the beautiful experiments defining the requirement for the major nutrients, vitamins and elements.Much of what we have on antioxidants is inspired conjecture.
Juice and dried fruits contain a mix of oxidized and unoxidized antioxidants but there is no way of knowing how much in each state. This relates to the argument that any antioxidant can also serve as a pro-oxidant, given the proper conditions. There are both water soluble and water insoluble antioxidants and we don’t know how important the ratio of, or absolue amounts of aqueous versus lipid solubility is for a health benefit.
There haven’t been any convincing studies with antioxidant supplements (mostly vitamin E) to prevent heart disease and it is likely the small benefit seen in some studies (on heart disease only, not on mortality) is due to the anti-coagulant effect of tocopherol. In fact, some studies clearly show harm in patients taking statins and antioxidants.
It is the whole diet, sufficient in its details that matters and is sustainable.

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Whole wheat

Dubcovsky et al Science 2006, 314, 1298-1301 have identified a gene in wild wheat which controls the distribution of nutrients to the grains when the leaves die off. Wild strains of wheat have an intact version of this gene NAM-B1 which can be crosed into domesticated wheat and increase yields.

Variability and memory of protein levels in human cell

Variability and memory of protein levels in human cells Sigal et al Nature 2006- 444-643-646
This paper looks at an important element of cell biology and hence metabolism and hence the influence of nutrition on metabolism and cell biology , that is the timescale over which protein concentrations mix in individual cells. Mixing meaning the time period over which cell lines reach the concentration that is characteristic of that cell. The authors looked at fluctuations over time of 20 endogenous proteins in living human cell tagged with a yellow fluorescent protein. Mixing between high and low concentrations occcured for all the proteins but the the levels of proteins from the same biological pathway fluctuated in more similar concentrations than other proteins in different pathways.
The random fluctuations in regulatory components are amplified as a signal cascade down a pathway. Alternatively long lived responses may result from feedback mechanisms.