Supplementary Materials – A healthy eating index to measure diet quality in pregnant women
Supplementary materials A. Details of scoring a diet with the HEI-SGP
Before each food item or ingredient is given a score, it is first scaled down to the amount (g)
per 1000 kcal consumed. This is explained using an example below.
Person XX , had a 2 white bread toast with a generous spread of butter for breakfast. With a
reported energy intake of 1200 kcal/day, 35g total fat, and 15g saturated fat from the butter:
Step 1: Total calories of food consumed in a day/1000 kcal = Divide factor
E.g. 1200 kcal/1000 kcal = 1.2
Step 2: Total weight of food per 1000 kcal = Total weight of individual food or ingredient/
divide factor
E.g. assuming the white bread toast weigh 120g in total
white bread: 120/1.2= 100g per 1000 kcal
Convert g/1000 kcal to servings/100 kcal.
E.g. 60g of white bread in the healthy dietary guideline is equivalent to 1 serving of total rice
and alternatives. So, 100g of white bread is equivalent to 1.25 servings per 1000 kcal
Step 3a: For adequacy components: total fruit, whole fruit, total vegetables, dark green leafy
and orange vegetables, total rice and alternatives, whole grains
Score =
total servings per 1000 kcal________________ x maximum score of component
total recommendation servings per 1000 kcal
The recommended amount of grains per 1000 kcal is 2.3 servings. Thus, a maximum score of
10 would be awarded for those who met the total rice and alternatives and tubers of 2.6
servings.
White bread toast= 1.25 /2.6 x 10 = 4.81
Therefore, consumption of 1.25 servings of total rice and alternatives would award Person XX
with a score of 4.81.
Step 3b: For moderation components: total fat, saturated fat
Score =
[Upper limit (g) – Amount consumed (g)] per 1000 kcal
[Upper limit (g) – Lower limit (g)] per 1000 kcal
x maximum score of component
E.g. assuming that the total fat and saturated fat from the butter consumed for that day was 35g
and 15g per 1000 kcal, respectively.
Total fat: (44.4-35) / (44.4-33.3) x 10 = 8.47
Saturated fat: (22.2-15) / (22.2-11.1) x 10 = 6.49
Therefore, consumption of 35g of total fat and 15g of saturated fat would award her with 8.47
and 6.49 points respectively.
Step 4: total score of HEI-SGP = (∑ score from each components/90) x 100
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Supplementary Materials – A healthy eating index to measure diet quality in pregnant women
e.g. assuming that two slices of white bread toast with butter was all that was eaten for the day,
Sarah would only have scored in the total rice and alternatives, total fat and total saturated fat
components.
Total score of HEI-SGP = [(4.81 + 8.47 + 6.49) /90] x 100
= 22.0
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Supplementary Materials – A healthy eating index to measure diet quality in pregnant women
Supplementary materials B. Sub group analyses of maternal characteristics by Healthy
Eating Index for pregnant women in Singapore (HEI-SGP) in the GUSTO cohort study
HEI-SGP score* GUSTO cohort
Low Tertile
Middle Tertile
High Tertile
(n=86)
(n=87)
(n=87)
1865 (519.8)
1924 (574.1)
1948 (584.8)
30.5 (4.7)
30.6 (4.7)
31.8 (4.55)
26.4 (4.5)
26.7 (4.6)
25.5 (3.4)
P†
Total energy (kcal) ‡
0.599
Age (years) ‡
0.150
BMI 26 weeks (kg/m²)‡
0.186
Ethnicity§
Chinese
44 (26.2)
65 (38.7)
59 (35.1)
<0.001
Malay
33 (55.0)
15 (25.0)
12 (20.0)
Indian
9 (28.1)
7 (21.9)
16 (50.0)
Gravidity§
First pregnancy
26 (31.0)
23 (27.4)
35 (41.7)
0.133
Not first pregnancy
60 (34.1)
64 (36.4)
52 (29.5)
Marital status§
Single, not living with husband
2 (40.0)
2 (40.0)
1 (20.0)
0.813
Married, living with husband
84 (32.9)
85 (33.3)
86 (33.7)
Educational status§
Primary/Secondary
23 (40.4)
23 (40.4)
11 (19.3)
0.024
Post-secondary
37 (38.5)
26 (27.1)
33 (34.4)
University and above
26 (24.3)
38 (35.5)
43 (40.2)
Work§
No
25 (37.3)
20 (29.9)
22 (32.8)
0.653
Yes
61 (31.6)
67 (34.7)
65 (33.7)
Household income category§
<S$2000
12 (46.2)
12 (46.2)
2 (7.7)
0.069
S$2000-5999
48 (32.0)
47 (31.3)
55 (36.7)
>S$6000
26 (31.0)
28 (33.3)
30 (35.7)
Smoking during pregnancy§
No
83 (32.5)
86 (33.7)
86 (33.7)
0.434
Yes
3 (60.0)
1 (20.0)
1 (20.0)
Smoking regular before pregnancy§
No
79 (33.5)
76 (32.2)
81 (34.3)
0.387
Yes
7 (29.2)
11 (45.8)
6 (25.0)
Alcohol use during pregnancy§
No
84 (32.8)
86 (33.6)
86 (33.6)
0.769
Yes
2 (50.0)
1 (25.0)
1 (25.0)
Alcohol usage before pregnancy§
No
58 (37.7)
46 (29.9)
50 (32.5)
0.137
Yes
28 (26.4)
41 (38.7)
37 (34.9)
Combined moderate and Strenuous
Exercise§
No
84 (33.1)
83 (32.7)
87 (34.3)
0.130
Yes
2 (33.3)
4 (66.7)
0 (0)
*HEI-SGP score range: lowest, 12.6-45.5; middle, 45.6-58.6; highest 58.7-94.3
† P-values obtained by one-way ANOVA tests for continuous variables and chi-square tests for categorical
variables.
‡ Values reflect the mean (standard deviation) for continuous variables
§ Values expressed as absolute numbers (percentage) for categorical variables; percentage may not add up due to
rounding
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Supplementary Materials – A healthy eating index to measure diet quality in pregnant women
Supplementary materials C. Foods included in Components of the Healthy Eating Index
for pregnant women in Singapore
The following lists are foods reported in GUSTO along with food ingredients suggested in the
HEI-2005 [28], grouped into HEI-SGP components, with reference to food groups
recommended for Pregnancy. Mixed dishes need to be identified as individual food ingredients
first before being placed into the components. Other foods or ingredients may be categorised
into the HEI-SGP components by using this list as a guide.
Total Fruit: acerola, apricot, avocado, apple, banana, blackberry, boysenberry, mandarin
orange/tangerine, calamansi/calamondin, currant, chiku, rock melon/cantaloupe, pomelo,
persimmon, papaya/paw paw, cranberry, huckleberry, blueberry, cherry, carrot juice, coconut,
durian, date, grape, grapefruit, guava, tamarind, jackfruit, kiwifruit, lemon, orange, mango,
watermelon, plantain, rhubarb, soursop/guanabana, starfruit, strawberry, ugli fruit, dragonfruit,
tamarind, atapchi/pine seeds, longan, rambutan, gingko, lychee, mangosteen, honeydew,
waterchestnut, water apple/jambu air, custard apple, pear, peach, pineapple, plum,
pomegranate, raisin, raspberry, and 100% juice made from these fruits
Whole Fruit: the above fruits in whole as fresh, dried, or in syrup. Excludes the juice forms
from the fruits listed above. Juice drinks using different percentages of real fruit juices to be
scored accordingly.
Total Vegetables: spring onion/jiu cai hua, onion, tomato, tomato juice, capsicum,
beansprouts, broccoli, cabbage, chinese cabbage, beetroot, bittergourd, carrot, cauliflower,
celery, chilli, leek, mushroom, chives, choko, corn, cucumber, eggplant/brinjal, french beans,
garlic, ginger, hairy gourd, sweetcorn/maize, thyme, herbs, tomato cherry, unspecified pale
green leafy vegetable, Jew’s ear, white fungus, winter melon/shark’s fin gourd, lettuce, long
beans, loofah, okra/lady’s finger, pepper, pickle, radish, iceburg lettuce, common cabbage/ko
lei/bao cai, chives/jiu cai, hum choy, szechuan preserved vegetable, jiu huang, four angle bean,
drumstick/kelur, snakegourd, chinese arrowhead/ci gu, fresh lily/bak hup, zucchini and all
vegetables listed in “dark green leafy and orange vegetable” below.
Dark green leafy and orange vegetables: arugula/rocket, beet greens, carrot, cilantro, winter
squash, chye sim, Coriander, spinach, seaweed, unspecified dark green leafy vegetable, kailan,
kangkong/water convuvolous, Chinese spinach/bayam pasir, kale, mint leaves, mustard
cabbage, mustard green, pumpkin, watercress, chinese spinach, parsley, xiao bai cai, di wang
cai, Shanghai pak choy, sang choy, hong kong chye sim, choy sam, ceylon spinach, Indian
mustard leaves/kai choy, tung ho/chrysanthemum leaves, wolfberry leaves/gou qi cai.
Total rice and alternatives and tubers: 3-in-1 cereal, appam, abacus beads, noodle (spinach
noodle/mee sua/ mian sian/ rice noodle/ hong kong noodle/mee tai mak/wanton noodle/kway
chap noodle/ mee/ yellow noodle/ kway teow/ tanghoon/sago noodle/ bee hoon/ ban mien/ mee
hoon kway/ udon /plain chee cheong fun/plain spaghetti/ linguine/ angel hair), breakfast
cereals, barley, bran, tortillas, pretzel, plain biscuit, green gram biscuits, cream cracker,
creamed filled biscuits*, iced biscuits*, marie biscuits, wheatmeal biscuits, bergedil*, cakes,
cookies, croissants, dougnuts, pastries, piecrust, pancake, , french bread, soft bread, fruit bread,
susi bun*, bun with fillings**, rice cakes, tapioca cake, chinese carrot cake, popcorn, potato,
chips*, corn/glutinous flour, idli, ketupat, kuih***, lontong ketupat, macaroni, waffles***,
wafer biscuit, wanton skin, youtiao*, Muruku*, naan, baked goods from plain flour***, plain
pow, plain roti prata, lotus root, yam/taro, and all grains listed in “whole grains”.
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Supplementary Materials – A healthy eating index to measure diet quality in pregnant women
Whole Grains: contain the entire grain kernel (bran, germ, and endosperm), oat,
oatmeal/wholemeal/multigrain baked goods, wholegrain/wholemeal cereals, brown rice, cha
soba/buckwheat noodle, chapatti, baked goods *** (cakes, cookies, croissants, dougnuts,
pastries, piecrust, pancake) from wholegrain flour.
Dairy: milk powder; cheese, evaporated milk, milk, flavoured milk*, whey protein
concentrate, yoghurt, raita, yoghurt drink, milo drink, milo powder, ovaltine powder, calciumfortified soymilk.
Total Protein foods: Abalone, anchovy, bak kua*, broad beans, black beans, kidney beans,
black eyed beans, mung bean, lentil, chickpea, black gram, petai/chou dou, urd bean, hyacinh
bean/lablab, batang, beef, sirloin steak, beef rending, beef patty, black chicken, tofu, canned
luncheon meat*, canned pure sardine, Egg (including bird egg), chicken, fried chicken wing**
fried chicken parts other than wing*, chicken floss*, char siew, vegetarian char siew (soy
product), chicken patty, crab stick*, crab ball*, mutton, dhal, eel, Pork, deep fried pork
cutlet**, cuttlefish, frankfurter*, grouper, ham, ham lean and fat*, squid, stingray, fish head,
prawn, shrimp, salmon, scallop, baby octopus, jellyfish, taukwa taupok, trevally, tofu, tuna, hee
keow, ikan bilis, red beas, yellow beans, soy beans, lap cheong*, lor bak*, mackerel, fish
paste*, mussel, Ngoh hiang*, otak otak*, otar*, pomfret, pork floss, pork belly*, spare ribs,
duck, meat sausage*, sea bass, scad, clam, cod soya bean curd.
Item contains other ingredients or very high in fat, and thus weight of actual main ingredient
should be adjusted. * x 90%; **x 80% ***x 50%. For protein foods consumed in a form where
parts other than meat contribute to weight of food e.g. fish head, use x 20% of cooked weight
Not included in any groups: Unfortified soymilk, offals e.g salmon roe; Lengkua/lengkua/beef
tongue, barley water, birdnest, belacan, non-dairy milk, water, oils and fats, condensed milk,
tea, spice powders, whole spice e.g. tumeric; tong chong chao; saffron, sauces, jams, creamer,
nuts.
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Supplementary Materials – A healthy eating index to measure diet quality in pregnant women
Supplementary materials D. Components of the Healthy Eating Index for pregnant
women in Singapore in comparison with HEI, AHEI, AHEI-P
HEI(14,23,24)
Adequacy components
AHEI-P(15); AHEI(16)
HEI-SGP
1
Total Fruit
Fruit
Total fruit
2
Whole Fruit
3
Total Vegetables
4
Dark green leafy and orange
vegetables
5
Dark Green and Orange
Vegetables and Legumes
Greens and Beans
6
Total Grains
Total rice and alternatives
7
Whole Grains
Whole grains
8
Milk
Dairy
9
Dairy
10
Meat (and beans)
11
Total protein foods
12
Seafood and Plant Proteins
13
Variety
Whole fruit
Vegetables
Ratio of white to red meat
Total vegetables
Total protein foods
Nuts and soy protein
14
Fibre
15
Calcium
16
Folate
17
Iron
18
Duration of vitamin use
Use of antenatal supplements
Moderation components
19
Sodium
20
Total Fat
Total fat
21
Saturated Fat
Saturated fat
22
Oils
23
Cholesterol
24
Calories from SoFAAS
25
26
Fatty Acids
(PUFA+MUFA)/SFA
Refined Grains
27
Empty Calories
Ratio of PUFA:SFA
28
Alcohol
29
Trans fat
Components in HEI-SGP reflects the Singapore dietary guidelines for pregnant women(9). Empty calories, alcohol,
fibre, trans fat, cholesterol, ratio of polyunsaturated fatty acids (PUFA) + monounsaturated fatty Acids (MUFA)/
saturated fatty acids (40), ratio of PUFA:SFA, refined grains, ratio of white to red meat, seafood and plant
proteins, variety, nuts soy protein were excluded as they are not reflected in the Singapore healthy eating
guidelines for pregnant women. Oils, milk, greens and beans have been accounted for in total fat, dairy
respectively. Greens and beans have been accounted for in dark green leafy and orange vegetables and total
protein foods. Calcium, folate, iron, and duration of vitamin use are accounted for in Use of antenatal supplements
(containing calcium, folate, iron), reflected in the guideline. Sodium and calories from solid fats, alcohol and
added sugar (SoFAAS) are excluded due to incomplete nutritional data of local food.
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