Transcript Potential strategies to improve micro

Reference:
P-181
Title:
POTENTIAL STRATEGIES TO IMPROVE MICRO-NUTRIENT INTAKE IN ADULT WOMEN WITH
SUBOPTIMAL VITAMIN AND MINERAL INTAKES AND STATUS
Authors:
Victoria Sharp, Toine Hulshof
The Problem:
Figure 1: Proportion of non-supplement taking adult women in the UK with
an average daily intake of micronutrients from food sources, below the LRNI
and RNI (Reference Nutrient Intake).8
Figure 1, shows that there are a significant proportion of adult women (19-64
years old) in the UK, whose average daily intake of some micro-nutrients is below
the Lower Reference Nutrient Intake (LRNI). The LRNI is the value that only
provides sufficient intake for 2.5% of the population. If the percentage of people
below the LRNI is larger than 5%, this is considered a micronutrient of concern. In
this population micronutrients of concern include iron, calcium, magnesium, vitamin
D and riboflavin as shown in Figure 1.
There are no current global figures for iron deficiency, but using anaemia as an
indirect indicator it can be estimated that most preschool children and pregnant
women in non-industrialised countries, and at least 30-40% in industrialised
countries, are suboptimal or deficient in iron.2
%
The National Diet and Nutrition Survey (NDNS) 2008 – 2012, is designed to assess
the diet, nutrient intake and nutritional status of the general population aged 1.5
years and over living in private households in the UK.1
RNI
100
90
80
70
60
50
40
30
20
10
0
LRNI
There are however, several strategies available to improve micronutrient intake.
Potential Strategies:
There are 3 relatively simple key strategies to help improve nutrient intake:
Change the daily diet by replacing current
food with that of higher nutrient density.
This is the most natural route as it doesn’t
involve supplementing the diet or consuming
fortified products; and therefore the risk of
overconsumption is very low.4 In the example
of iron, there is evidence that higher
consumption of foods naturally rich in iron
leads to increased intakes and improved iron
status, however this requires an initial change
in eating behaviour. 4 The bioavailability of
micronutrients is important in determining
how much of the intake is available for the
body. Factors that will affect this should be
considered when altering the diet to improve
micronutrient status. For example, iron
absorption can vary from 1% to 40%
depending on other dietary factors. Some of
these factors are outlined in Table 1.
Although this is often referred to as the most
sustainable approach, there may be some
constraints to this strategy.7 For example,
economic constraints may contribute to
unhealthy food choices resulting in suboptimal
micronutrient intakes and some sub groups of
this population aren’t often considered in
advice.6 For example, women who are
following a vegan diet and would therefore
avoid any product of animal origin.
Increase the amount of foods in the diet with added
vitamins and minerals.
This strategy reaches a large proportion of the population
whilst requiring no or very little action on the consumers
part.3 Although consumers don’t need to change their
habitual dietary patterns, strong and impactful
advertising and labelling may be needed from
manufacturers or governments to highlight fortified
foods to consumers.3 In order to be successful with
consumers, fortified foods need to be the same price as
comparable foods as well as tasting the same.3
Fortification, especially mandatory fortification, will on
the other side capture people who don’t necessarily
need or want it.
Table 1: Dietary factors that can potentially enhance or inhibit iron absorption.4
Enhancing Factors
Inhibiting Factors
Lean red meat (haem iron)*.
Calcium, particularly from milk
and dairy products.
Oily fish, such as salmon and
sardines.
Phytates, present mainly in
cereal bran, grains, legumes, nuts
and seeds.
Iron-binding phenolic
compounds (polyphenols,
tannins), which are present in
tea, coffee, herbal infusions and
leafy green vegetables.
Vitamin C, for example fresh
fruit and juices.
Fermented products, such as
soy sauce and bread (reduce
the effect of phytates).
Use of micro-nutrient supplements
in addition to the normal diet.
Iron supplementation is an effective
strategy to improve the iron intake
of an individual and is particularly
effective at targeting specific groups
in need, such as pregnant women or
vegans.7 However, the NDNS reports
that supplement takers in all age
and sex groups had a higher mean
intakes of all minerals from food
sources compared with nonsupplement takers.1 This suggests
that individuals who really need
supplements are often the ones not
taking them. Studies have also
shown that even during times when
supplements have proven to be
beneficial, for example folic acid
supplements during pregnancy,
women in the UK continue with
their established behaviours and are
reluctant to adapt when it requires
effort, money or doing something
unfamiliar.3 Due to the relatively
high levels of the micro-nutrients in
supplements, it has the highest risk
for overconsumption of certain
vitamins and minerals.
*Iron is generally better absorbed when consumed from meat rather than
plant-based food sources.4
Conclusions
 All of the 3 strategies can have a positive impact on micro-nutrient intake but the effectiveness of one, or a combination of these approaches, may
depend on which micronutrient status needs to be improved.
 Lifestyle and other dietary factors need to be taken into consideration when looking at the most effective strategy.
 Different strategies are needed on an individual and population level; on an individual level it might be most effective to use a combination of
strategies. However, from a public health perspective fortification seems to be the cheapest and most effective strategy.
 Supplementation is a valuable option for ensuring that vulnerable subgroups, such as vegans and pregnant women, can meet the RNI.
References:
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Bates et al (2014) National Diet and Nutrition Survey. Results from Years 1-4 (combined) of the Rolling Programme (2008/2009 – 2011/12)
World Health Organisation (2001) Iron Deficiency Anaemia – Assessment, Prevention and Control.
Tedstone, A. et al (2007) Fortification of selected foodstuffs with folic acid in the UK: consumer research carried out to inform policy recommendations. Journal of Public Health. 30 (1) 23 – 29.
Derbyshire, E (2010) Iron deficiency anaemia in pregnancy – what are the solutions? Nutrition and Food Science. 40 (6) 598 – 607.
Rickard AP. et al (2009) An algorithm to assess intestinal iron availability for use in dietary surveys. British Journal of Nutrition. 102 (11) 1678-1685.
Darmon, N. et al. (2002) A cost constraint alone has adverse effects on food selection and nutrient density: An analysis of human diets by linear programming. The Journal of Nutrition. 132 (1) 3764 – 3771.
Gautam, C. et al. (2008) Iron deficiency in pregnancy and the rationality of iron supplements prescribed during pregnancy. The Medscape Journal of Medicine. 10 (12) 283.
DE VRIES, J. (2016) Personal information.