This project examines the feasibility of a smartphone-based intervention to reduce obesity and breast cancer risk among Chinese American women in San Francisco. The proposed intervention is to use the mobile application and an activity tracker device to promote a healthier lifestyle and physical activity. Ultimately, the findings will advance the NIH mission of enhancing health promotion and disease prevention.

Cancer is the leading cause of death in women in the United States (US). Chinese Americans are the largest ethnic group among Asian Americans. Although the incidence of breast cancer, the most common cancer in women, has decreased among other U.S racial groups over the last 15 years, Chinese American women in California have experienced a significant increase of incidence of 1.1% from 1998 to 2013. Studies have found that assimilation stress and obesity are associated with increased risk for breast cancer in Chinese American women. There are no existing interventions targeted at breast cancer prevention among premenopausal mothers with abdominal obesity. Interventions tailored to an individual's cultural, lifestyle and social support system are needed to reduce obesity and breast cancer risk. A smartphone-based intervention provides a promising platform for obesity and cancer prevention. The overall goal of this project is to test the feasibility of an obesity and breast cancer prevention intervention among Chinese American women in San Francisco. The investigators will adapt the Healthy Mothers Healthy Children: Technology-Based Intervention to Prevent Obesity to reduce obesity and breast cancer risk in premenopausal women with abdominal obesity who have dependent children in San Francisco. The proposed intervention ("Smartphone-Based Cancer and Obesity Prevention Program for Chinese Women: SCOPP-CW) includes 12 weekly educational modules and six bi-weekly tailored messages delivered via WeChat, a popular private communication app used by Chinese and Chinese Americans. The investigators propose to conduct a pilot randomized control study (RCT) to assess the short-term efficacy of SCOPP-CW on abdominal obesity, breast cancer knowledge and attitudes, weight-related behaviors (food intake and physical activity), and metabolic risk (blood pressure, lipid profile, hemoglobin A1c), which are associated with breast cancer. Thus the investigators propose the following aims: (1) Aim 1: To estimate the preliminary efficacy of the SCOPP-CW intervention on the primary outcomes (i.e. waist circumference and breast cancer knowledge and attitudes) and secondary outcomes (i.e. body mass index, self-efficacy, food intake, physical activity at baseline, 3 months, and 6 months, and metabolic risk [blood pressure, hemoglobin A1C, and lipid panel]) at baseline and 6 months.

Aim 2: To assess feasibility by understanding participants' acceptance, barriers to adherence and recommendations for intervention using focus group interviews. The investigators anticipate that this intervention will have a significant impact on breast cancer prevention. The investigators plan to use the proposed pilot study's findings to conduct a larger scale randomized trial (R01) to test the long-term efficacy of the intervention.

Inclusion Criteria:

• be female
• be at least 18 years old
• have a waist circumference great than 80 cm
• own a smartphone
• be able to read Chinese and speak Mandarin
• be premenopausal
• have a child between the age of 1 and 18 years old.

Exclusion Criteria:

• are pregnant
• gave birth less than 12 months prior to enrollment date
• have a history of breast cancer
• have an acute or life-threatening disease (e.g., renal failure).

female