Download A Focus on Nutrition: Key findings from the 2008

Committee for Healthy Ageing
Bulletin No 9, March 2012
Welcome to the ninth issue of the quarterly Bulletin of the New Zealand Nutrition Foundation Committee
for Healthy Ageing. The committee, a special interest group of the Foundation, was initially established in
2004, to champion the cause for improving the quality of life of older New Zealanders, through nutrition
and physical activity. Each quarter, this bulletin updates you on issues of importance or topical interest in
relation to optimal nutrition and physical activity of older people.
In this issue, we focus on the Ministry of Health’s Adult Nutrition survey. Data were collected in 2008-09,
and released late last year. The previous Nutrition Survey was conducted in 1997, and it is interesting to see
how the diets of older people have changed during the intervening years.
A Focus on Nutrition: Key findings from the 2008-09 NZ Adult Nutrition Survey
Both the 1997 and 2008-09 surveys had a similar number of participants – 4636 vs 4721. All respondents
lived in the community, with those living in institutions excluded. The data in both surveys are broken down
by age, ethnicity and socio-economic level (quartiles in 1997 and quintiles in 2008-09). We focus here on
men and women 71+ years old, although the older age cut-off point in 1997 was 65+ years and any
comparisons made are aligned with that group.
Food and nutrient intakes
The table below provides a comparison of intakes for selected nutrients between the two surveys and the
recommended amounts.
Table 1: Median results for selected nutrients
Nutrient
Energy (kJ)
Protein (g)
Dietary fibre (g)
Vitamin C (mg)
Vitamin B12 (µg)
Calcium (mg)
Iron (mg)
Zinc (mg)
Selenium (µg)
NNS 97
Male 65+
9161
83
22
95
4.0
751
12.2
11.6
43
Female 65+
6449
61
19
94
2.9
636
9.2
8.9
36
NNS 2008-09
Male 71+
7926
78
20.4
96
4.2
743
11.4
9.7
52
Female 71+
6014
60
17.1
89
2.7
676
8.9
7.6
39.5
RDI (Aust & NZ 2006)
Male 70+
Female 70+
81
30
45
2.4
1300
8.0
14.0
70
57
25
45
2.4
1300
8.0
8.0
60
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Protein intake was estimated to be inadequate in 13.4% males and 15.5% females 71 years and older. Adult
New Zealanders derive the greatest proportion of protein from breads, with older people having a higher
percentage of their protein from this source than any other group. Milk is the second highest contributor of
protein for this age group.
Milk also provided 34 and 31.7% of the calcium intake for older men and women respectively; a greater
percentage than for any other age group. Calcium intakes were lower in older men than younger, and while
older women had lower intakes than women aged 31-70 years, they had about the same (just slightly less)
as women aged 15-30 years. Of possible concern is the inadequate intake reported in 86% males and 92.8%
females aged 71+ years, but the report states “Interpretation of these data requires a cautionary approach
because the EAR (estimated adequate requirement) values have been augmented by 320 mg to take into
account ‘unspecified low absorption that occurs at about 500 mg/day’ (NHMRC 2006). Also, the addition of
260 mg/day to the EAR for adults aged 71+ years, to account for further decreases in absorption with age, is
high and is reflected in the higher prevalence of inadequate intake for older age groups in all ethnic groups.
While calcium is of major importance for attaining and maintaining bone health, other factors such as
vitamin D intakes, exercise levels, and habitual levels of intake all influence bone health.”
The percentage of respondents choosing lower-fat or trim milk most of the time increased with age in both
genders, with those 71+ topping the scale. Almost two thirds of women 71+ chose lower fat milks, but their
calcium intake remained only just over half the RDI for their age.
The median percentage of energy from fat for both older men and women was 33%. By far the greatest
contributor of fat to the diet was butter and margarine, at around 15%; approximately a third higher than
for those 51+ years old. Over 87% older respondents used oil most of the time for cooking; a similar level to
the rest of the sample population.
Older men obtained a greater percentage of their fibre intake from bread, vegetables and fruit than
younger males, and women from bread and fruit. Fruit consumption was higher in older men in this latest
survey compared to 1997, but they were still less likely than their female counterparts to meet the
recommended 2 servings a day. Older men and women obtained noticeably less fibre from grains and
pasta, compared with younger adults (especially the 19-30 year-olds).
A higher percentage of older men and women ate grainy breads most of the time. However, the number
who met the breads and cereals guideline of 6+ servings a day was not ascertained. In 1997, the older age
group was less likely than younger people to meet this guideline. As we might expect, however, a higher
proportion of older adults (>95%) ate breakfast each day than those in younger age groups. Less than 50%
of people aged 19-30 ate breakfast on a daily basis.
About 27% of the daily iron intake came from bread and breakfast cereals for the older age group; a higher
percentage than for other adults. Meat, poultry, fish and seafood supplied 17.9% and 17.1% of the iron in
the diet for older men and women respectively.
Between 40 and 50% of all in the study sample ate red meat 3-4 times per week, with little difference
among age levels. Approximately 50-60% ate chicken 1-2 times per week, with the lowest level being 19-30
year old males (49.5%) and young women, 15-18 years old (46.2%). Just over 41% across the whole
population ate fresh or frozen fish or shellfish at least once per week, with about 52% of men and women
aged 51+ meeting this level of consumption. More 71+ year old adults removed excess fat from meat and
skin from chicken regularly.
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Zinc, like iron, is widely available in a range of foods, but is more bioavailable from animal sources. Intake
by older men and women was lower than from any other age group, and lower than shown in the 1997
survey. The estimated prevalence of inadequate vitamin B12 intake in women of 71+ years was 27%,
compared with 1.1% in those aged 51-70 years.
The selenium content of plant foods is dependent on the selenium content of the soils in which they are
grown. In New Zealand, soils have a lower selenium content. Breads made from Australian wheat are
therefore likely to have a higher selenium content than those made with NZ wheat. However, this
difference was not adjusted for in the analyses of the 24-hour recall diets for selenium.
General findings included a similar proportion of older respondents never or rarely added salt to food after
it had been cooked to the population average of 43.1% of men and 52.2% of women. An average of 84.2%
used iodised salt, rising slightly amongst older people, although about a quarter of respondents did not
know whether the salt used at home was iodised or not. Of those who consumed alcohol, 66.5% came
from wine for older women, with spirits contributing 19.5%. For men, 42.9% came from beer, 35.1% from
wine and 16.9% from spirits.
Supplement usage
When asked about use of dietary supplements in the last year, 49.2% of the women and 38.4 males 71+
years reported taking them (see table 2); fewer than in younger groups, with the exception of 15-18 year
olds. However, ‘regular’ (once or more a week), rather than ‘occasional’ (less than once a week), usage was
greater in the older age group.
Table 2: Percentage of the older population consuming dietary supplements in the last year
Regular use
Occasional use
NNS 97*
Male
17
5
Female
27.5
7
NNS 2008/09
Male
33.4
5
Female
42.2
5
* - percentages calculated from an amalgamation of vitamin & mineral supplements with Other supplements
The most popular supplements for this age group were oils (including fish oils, omega 3 products,
flax/linseed oil, evening primrose oil), followed by glucosamine/chondroitin. Percentage usage was higher
for these supplements than in other age groups. Multivitamins came third, but percentages of older people
taking these was lower than for 19-50 year old men and all younger women.
Prevalence of obesity
The rate of obesity was highest in the younger age groups, dropping to 24.4% in the 71+ age group (see
table 3). Research suggests older people in the overweight category have a decreased risk of mortality than
those who are underweight, although risk increases again with obesity. It is encouraging to note
approximately 75% of older men and women fall into the normal and overweight category.
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Table 3: Body size – percentage of older adults
NNS 97
75+ years
Underweight
(BMI <18.5 kg/m2)
Normal weight
(BMI 18.5-24.9 kg/m2)
Overweight
(BMI 25-29.9 kg/m2)
Obesity
(BMI >30 kg/m2)
NNS 08-09
71+ years
Male
n/a
Female
n/a
Male
0.5%
Female
2.6%
n/a
n/a
23.2%
34%
38.9%
33.3%
51.9%
39.1%
7.4%
17.3%
24.4%
24.4%
Food Security
In both surveys, the older age group was most ‘food secure’, with 97 and 98% of women and men in 1997
and 92.1 and 92.6% women and men in 2008-09 considering they could always afford to eat properly. In the
recent survey, this age group had the highest percentage reporting this positive trend.
Note: While we have attempted to compare findings from the 1997 and the 2008-09 surveys to identify
trends, care must be taken in interpreting the data if using them for accurate comparisons. Please refer to
the original documents. While much of the research methodology is the same, the most notable
discrepancy has been the cut-off ages – 65+ or 75+ in NNS 97, 71+ in the 2008-09 survey. We believe,
however, the information presented here gives a good overall picture of the situation as it stands today.
The
full
document
is
available
on
the
Ministry
of
Health
website
http://www.health.govt.nz/publication/focus-nutrition-key-findings-2008-09-nz-adult-nutrition-survey
References:
Ministry of Health.1999 NZ Food: NZ People Key results of the 1997 National Nutrition Survey. Wellington. Ministry of Health.
University of Otago and Ministry of Health. 2011. A Focus on Nutrition: Key findings of the 2008/09 New Zealand Adult Nutrition
Survey. Wellington: Ministry of Health.
Flicker L, McCaul KA, Hankey GJ et al. Body mass index and survival in men and women aged 70-75. J Am Geriatr Soc 58:234-41,
2010
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