Women's empowerment relates to women's ability to make life choices (158). Higher levels of empowerment were associated with increased income, household decision-making, control over resources, and utilization of health resources (5, 158–160). For nutrition outcomes, empowerment was associated with increased income allocated to food expenditures and improved household food security (160, 161). It was also associated with increased dietary diversity, but had no impact on women's BMI (5, 161, 162). For example, mothers’ participation in empowerment activities through Helen Keller International's Enhanced Homestead Food Production (EHFP) program in Burkina Faso was associated with increased fruit intake (difference-in-differences = 15.8 percentage points, P = 0.02) and nearly statistically significant increases in meat intake and dietary diversity (163). Participation was also associated with decreased prevalence of underweight (difference-in-differences = −8.7 percentage points, P < 0.01) but not overall mean BMI (163). In addition, the EHFP program in Bangladesh and Nepal was associated with decreasing trends in maternal anemia (anemia prevalence decreased by a magnitude of 12%, P = 0.075 in Bangladesh, and 26%, P = 0.009 in Nepal) (160). However, this was not consistent with findings from Cambodia (160).
Nutrition education, including communication and counseling to raise awareness and promote nutrition-related knowledge and behaviors aligned with public health goals, was found to increase women's knowledge and improve women's dietary diversity and protein intake (15–21). It also reduced energy intake of overweight women over a 9-mo period (22). However, evidence for the effectiveness of nutrition education interventions showed mixed impact on biological and anthropometric markers of women's nutritional status (14–16, 18, 23–29). This could be due to lack of statistical power given the small sample sizes of the reviewed studies. For adolescent girls, nutrition education was found to reduce odds of overweight, and improve knowledge, dietary intake, physical activity, and sedentary behavior (27, 29, 30). This was particularly true for nutrition education that lasted longer than 12 mo (29). Nutrition education was also more strongly associated with changes in health outcomes in studies evaluating childhood obesity treatment, rather than childhood obesity prevention (29).
Dietary fiber is found in plant foods like whole-grain breads and cereals, beans and peas, and other vegetables and fruits. At least one study suggests that women who eat high amounts of fiber (especially in cereal) may have a lower risk for heart disease. High-fiber intake is also associated with lower cholesterol, reduced cancer risk and improved bowel function. And one long-term study found that middle-aged women with a high dietary fiber intake gained less weight over time than women who ate more refined carbohydrates, like white bread and pasta.
Lipid-based nutrient supplement (LNS) programs are intended to enrich diets with micronutrients and essential fatty acids (97), and are often used in emergency settings to meet nutritional needs of pregnant and lactating women (98). Of the studies that report on women's health outcomes, LNSs provided to pregnant and lactating women increased body weight and midupper arm circumference, particularly of multiparous women and women >25 y of age (99). They were associated with increased plasma α-linoleic acid, although not plasma lipids and other fatty acids (100). LNSs did not affect women's immune responses, particularly pregnant women's anti-malarial antibody responses (101). There was limited evidence connecting LNS supplementation to unhealthy weight gain and retention, and this is being explored in ongoing studies in Ghana (97).
Changes in the way research ethics was visualised in the wake of the Nuremberg Trials (1946), led to an atmosphere of protectionism of groups deemed to be vulnerable that was often legislated or regulated. This resulted in the relative underrepresentation of women in clinical trials. The position of women in research was further compromised in 1977, when in response to the tragedies resulting from thalidomide and diethylstilbestrol (DES), the United States Food and Drug Administration (FDA) prohibited women of child-bearing years from participation in early stage clinical trials. In practice this ban was often applied very widely to exclude all women. Women, at least those in the child-bearing years, were also deemed unsuitable research subjects due to their fluctuating hormonal levels during the menstrual cycle. However, research has demonstrated significant biological differences between the sexes in rates of susceptibility, symptoms and response to treatment in many major areas of health, including heart disease and some cancers. These exclusions pose a threat to the application of evidence-based medicine to women, and compromise to care offered to both women and men.