Table 2.
Participant characteristics by frequency of green tea intake
| Less than weekly intake (< once per week) | Weekly intake (1-6 times per week) | Daily intake (7+ times per week) | P value* | ||||
|---|---|---|---|---|---|---|---|
| |
mean |
s.d. |
mean |
s.d. |
mean |
s.d. |
|
|
Age (y)* |
45.4 |
6.8 |
48.3 |
8.2 |
49.7 |
7.0 |
0.01 |
|
Body Mass Index (kg / m2) |
21.9 |
3.3 |
22.0 |
3.1 |
21.0 |
2.8 |
0.18 |
| |
n |
row % |
n |
row % |
n |
row % |
|
|
Menopausal status / menstrual phase |
|
|
|
|
|
|
0.049 |
| Premenopausal women in luteal phase |
62 |
52.1% |
32 |
26.9% |
25 |
21.0% |
|
| Postmenopausal |
25 |
34.7% |
23 |
31.9% |
24 |
33.3% |
|
|
Study center, n (%) |
|
|
|
|
|
|
0.01 |
| Hawaii |
70 |
55.1% |
34 |
26.8% |
23 |
18.1% |
|
| Los Angeles |
7 |
21.9% |
13 |
40.6% |
12 |
37.5% |
|
| San Francisco |
10 |
31.3% |
8 |
25.0% |
14 |
43.8% |
|
|
Combined parity and age at first birth, n (%) |
|
|
|
|
|
|
0.07 |
| Nulliparous |
12 |
42.9% |
8 |
28.6% |
8 |
28.6% |
|
| 1st birth age ≤ 20 y |
7 |
63.6% |
4 |
36.4% |
0 |
.0% |
|
| 1-2 live births / age ≥ 21 |
53 |
52.5% |
23 |
22.8% |
25 |
24.8% |
|
| 3+ live births / age ≥ 21 |
15 |
29.4% |
20 |
39.2% |
16 |
31.4% |
|
|
Age at menarche, n (%) |
|
|
|
|
|
|
<0.001 |
| ≥ 12 y |
56 |
54.9% |
34 |
33.3% |
12 |
11.8% |
|
| > 12 y |
31 |
34.8% |
21 |
23.6% |
37 |
41.6% |
|
|
Born in Asia, n (%) |
|
|
|
|
|
|
<0.001 |
| No |
74 |
49.3% |
49 |
32.7% |
27 |
18.0% |
|
| Yes |
13 |
31.7% |
6 |
14.6% |
22 |
53.7% |
|
|
Soy intake (frequency of weekly intake), n (%) |
|
|
|
|
|
|
<0.001 |
| 0-0.5 times weekly |
31 |
66.0% |
12 |
25.5% |
4 |
8.5% |
|
| 0.5-1 times weekly |
27 |
47.4% |
20 |
35.1% |
10 |
17.5% |
|
| > once weekly |
29 |
33.3% |
23 |
26.4% |
35 |
40.2% |
|
|
Black tea (frequency of weekly intake), n (%) |
|
|
|
|
|
|
0.21 |
| < once weekly |
69 |
50.7% |
34 |
25.0% |
33 |
24.3% |
|
| 1-6 times weekly |
12 |
32.4% |
15 |
40.5% |
10 |
27.0% |
|
| 7+ times weekly |
6 |
33.3% |
6 |
33.3% |
6 |
33.3% |
|
|
Coffee (frequency of weekly intake), n (%) |
|
|
|
|
|
|
0.75 |
| 0-2 times weekly |
22 |
53.7% |
11 |
26.8% |
8 |
19.5% |
|
| 3-13 times weekly |
25 |
41.0% |
18 |
29.5% |
18 |
29.5% |
|
| ≥14 times weekly |
40 |
44.9% |
26 |
29.2% |
23 |
25.8% |
|
|
Caffeine (weekly intake in mg), n (%) |
|
|
|
|
|
|
0.83 |
| 0-734 |
29 |
50.0% |
15 |
25.9% |
14 |
24.1% |
|
| 734-1609 |
27 |
47.4% |
15 |
26.3% |
15 |
26.3% |
|
| ≥1610 | 31 | 40.8% | 25 | 32.9% | 20 | 26.3% | |
* For continuous covariates, p-values were obtained using ANOVA and reflect significance of differences between means by categories of green tea intake. For categorical covariates, p-values were obtained using Chi Square tests and reflect differences in distribution.