Table 2 Comparison of reported dairy consumption across different age groups

Bai et al. 2008 [89]

638

Qingdao; 2005

Total population,

37.95 (13.51)^a

Age groups^bc,

< 30

30 - 50

> 50

Milk,

< 30 years: N/R

30 - 50 years: N/R

> 50 years: N/R

Middle-aged (30 - 50) consumers are likely to consume less fluid milk than those aged under 30 years or over 50 years. and also less likely to be a fluid milk consumer.

Ba et al. 2013 [73]

1329^d

Beijing;

N/R

Total population,

N/R

Age groups^bce,

18 - 44

45 - 59

≥ 60

Milk,

18 - 44 years: 75.8 g/d

45 - 59 years: 96.6 g/d

≥ 60 years: 163.4 g/d

The elders had higher intakes of milk than other groups.

Zong et al. 2014 [79]

1202^f

Beijing, Shanghai;

2005

Total population,

N/R

Age groups^cf,

50 - 70, n = 1202

Total dairy,

Amount of intake not reported.

Participants with higher dairy intake at baseline were more likely to be younger.

Xu et al. 2015 [55]

2745

Multiple cities (provinces) A; 2009

Total population,

(age range: ≥ 60)

Age groups^c,

60 - 69, n = 1563

≥ 70, n = 1182

Total dairy,

(median intake, IQR)

Male,

60 - 69 years: 200 g/d, 87 - 250 g/d

≥ 70 years: 162 g/d , 83 - 250 g/d

Female

60 - 69 years: 167 g/d, 83 - 234 g/d

≥ 70 years: 167 g/d, 83 - 241g/d

Only 10% of older people consumed dairy. For those who consumed dairy, males aged between 60 and 69 years had higher intakes of dairy products than those aged over and 70 years.

Cheng et al. 2015 [45]

1018^d

Beijing, Harbin;

2010

Total population,

N/R

Age groups^ce,

18 - 60^b

> 60, n = 43^g

Milk,

Amount of intake not reported.

Among urban residents, the elderly population (over 60 years) had higher consumption of milk compared to other residents (18 to 60 years).

He et al. 2016 [46]

N/R

N/R

Total population,

N/R

Age groups^bc,

18 - 44

45 - 59

≥ 60

Total dairy,

Amount of intake not reported.

The frequency of dairy intake decreased with aging.

Liu et al. 2016 [69]

16612

National;

2010 - 2012

Total population,

N/R

Age groups^c,

60 - 69, n = 10309

≥ 70, n = 6303

Total dairy,

60 - 69 years, 28.49 g/d

≥ 70 years, 39.57 g/d

People aged 70 and over had significant higher dairy intakes than elders aged between 60 and 69. (P < 0.001)

Tian et al. 2017 [47]

14452

Multiple cities (provinces) B;

2004, 2006, 2009, 2011

Total population,

42.8 (10.3)^a

Age groups^c,

20 - 39, n = 5296

40 - 59, n = 9156

Total dairy,

20 - 39 years: 13.0 (47.1)^a g/d

40 - 59 years: 14.2 (55.8)^a g/d

People aged 40-59 had a higher consumption of dairy products compared to those aged 20 - 39, but this was not statistically significant. (P > 0.05)

Wang et al. 2017 [63]

4221

Multiple cities (provinces) A;

1989 - 2011

Total population,

N/R

Age groups^c,

18 - 39, n = 1796

40 - 59, n = 2425

Total dairy,

18 - 39 years,

1989, 2.12 (24.28)^a g/d

1991, 3.03 (27.41)^a g/d

1993, 2.74 (24.87)^a g/d

1997, 3.48 (34.29)^a g/d

2000, 5.44 (38.75)^a g/d

2004, 12.49 (52.51)^a g/d

2006, 12.44 (72.14)^a g/d

2009, 10.70 (47.51)^a g/d

2011, 28.29 (82.02)^a g/d

40 - 59 years,

1989, 1.77 (19.56)^a g/d

1991, 4.80 (38.96)^a g/d

1993, 4.79 (34.86)^a g/d

1997, 3.16 (24.41)^a g/d

2000, 7.26 (38.71)^a g/d

2004, 15.37 (66.36)^a g/d

2006, 13.47 (65.34)^a g/d

2009, 12.07 (63.97)^a g/d

2011, 25.46 (84.75)^a g/d

The dairy consumer aged 18 - 39 had higher intakes of dairy products than people aged 40 - 59 but with no significant difference. (P > 0.05)

Huang et al. 2019 [62]

4921

Multiple cities (provinces)C ;

2015

Total population,

N/R

Age groups^c,

60 - 79, n = 4490

≥ 80, n = 431

Total dairy,

(reported intake; percentage of consumer)

60 - 79 years, 200.0 g/d; 19.6%

≥ 80 years, 250.0 g/d; 26.2%

Elders aged 80 and over had a significant higher daily intake of dairy products than those aged 60 - 79. (P < 0.001); In addition, elders also had a significant higher percentage of consumers of dairy products than those aged 60 - 79. (P < 0.05)

Na et al. 2022 [64]

14711

Multiple cities (provinces) B; 1991, 1993, 1997, 2000, 2002, 2004, 2006, 2009, 2011

Total population,

42.0 (32.0, 54.0)

Age groups^bc,

N/R

Compare to groups of no dairy consumption and 0.1 - 100 g/d, participants in group of dairy consumption more than 100 g/d tended to be older. The median (IQR) age at baseline of the higher (> 100 g/d), lower (0.1 - 100 g/d) consumption and non-consumption groups had significant difference. (P < 0.001)

Wang et al. 2022 [65]

6320

Multiple cities (provinces) D;

1991, 2000, 2015

Total population,

N/R

Age groups^c,

60 - 69, n = 3853

≥ 70, n = 2467

Total dairy,

60 - 69 years, 16.3 g/d

≥ 70 years, 26.1 g/d

Older people (≥ 70) had significant higher consumption of dairy than people in group 60 - 69 years. (P < 0.05)