Dolores Penafiel, Holger Cevallos-Valdiviezo, Ramón Espinel, Patrick Van Damme
7 min
This 2019 study by Penafiel et al. examines how traditional foods—locally cultivated and wild species—shape the diets of indigenous women in rural Guasaganda, Ecuador. Amid challenges like malnutrition and hidden hunger in developing countries, the researchers assess whether these foods enhance dietary diversity and nutrient adequacy. Using rigorous methods like repeated 24-hour recalls, they reveal that traditional foods provide 38.6% of energy intake and significantly boost overall diet quality, making a case for promoting them in public health strategies.
Traditional foods (TF) are defined here as edible species from local and wild sources, culturally embedded in indigenous communities. In rural Ecuador, they contribute substantially to nutrition: 38.6% of total energy, meeting daily needs for protein, carbohydrates, iron, and vitamin C. The study highlights TF's role in combating 'hidden hunger'—micronutrient deficiencies—by supplying a high share of essential vitamins and minerals, even if not the bulk of energy.
Diet quality is quantified using the Mean Adequacy Ratio (MAR), which averages Nutrient Adequacy Ratios (NAR) for key macro- and micronutrients. The women's diets scored an MAR of 0.78, indicating good but not perfect adequacy. Dietary Species Richness (DSR) counts unique food species consumed, while Minimum Dietary Diversity for Women (MDD-W) tracks variety across 10 food groups. These metrics show that higher TF consumption directly improves MAR: each extra level of local species intake raises macronutrient MAR by 0.033 and micronutrient MAR by 0.052 (both p<0.001).
To capture 'usual' intake, the study employed the Multiple Source Method (MSM): repeated 24-hour dietary recalls (spaced 14 days apart) combined with consumption frequency data. Participants—non-pregnant, non-breastfeeding indigenous women over 18, residents for >1 year—detailed foods by amount, local names, sources (e.g., home-grown, wild-collected), and preparation. Missing data (11 visits) was imputed via multivariate chained equations. Surveys occurred during the rainy season to document edible TF, ensuring cultural relevance.
Increasing TF use enhances food biodiversity, linking species richness to nutrient security. In resource-poor rural settings, where women prepare meals, TF reliance diversifies diets beyond staples, improving macro- and micronutrient profiles. Statistical models (linear quantile mixed effects) confirm associations between DSR, local species consumption, and MAR, independent of age, education, or occupation. This supports interventions promoting TF cultivation to elevate diet quality and fight malnutrition.
OBJECTIVE: To evaluate the dietary diversity and the nutrient contribution of traditional foods (locally cultivated and wild) by conducting a food intake study in rural Ecuador. DESIGN: Repeated 24 h recalls over a 14 d interval and frequency of consumption served to simulate the usual diet by the Multiple Source Method. Data on missing visits (n 11) were imputed using multivariate imputation by chained equations. The intakes of three macro- and six micronutrients were reported. Nutrient Adequacy Ratios, Mean Adequacy Ratio (MAR), Dietary Species Richness (DSR) and Minimum Dietary Diversity for Women were used as measures of dietary quality. A linear quantile mixed model was used to investigate the association between DSR, local species, MAR, age, education and occupation. SETTING: Guasaganda, Cotopaxi (Ecuador). PARTICIPANTS: Rural, indigenous adult women, non-pregnant and not breast-feeding. RESULTS: The studied diet had MAR of 0·78. Consumption of traditional foods contributed 38·6 % of total energy intake. Daily requirements for protein, carbohydrates, Fe and vitamin C were reached. An extra level of consumption of local species was associated with an increase in median MAR for macronutrients of 0·033 (P < 0·001). On the other hand, an extra level of consumption of local species was associated with an increase in median MAR for micronutrients of 0·052 (P < 0·001). CONCLUSIONS: We found statistical evidence that traditional foods contribute to adequate intakes of macro- and micronutrients and dietary diversification in the studied population. Future public health interventions should promote the cultivation and consumption of traditional foods to increase the quality of the local diet.
Alex: So with all that detail on sources—like wild-picked or home-grown—they could link more species directly to better nutrient scores.
Sam: Precisely. They counted every unique edible plant or animal species reported in the women's diets. That total gives a picture of how varied the overall eating was—called Dietary Species Richness, or DSR. Separately, they focused on just the local or wild-gathered ones, like home-grown squash or forest berries, ignoring imported staples. That's the Traditional Food Diversity Score, or TFDS, with a median of six in this group. Each additional local species linked to higher scores for both energy-giving and micronutrients.
Alex: Got it—a simple headcount of types eaten, split by local versus not. And to check if that variety actually filled nutrient gaps, they compared intakes against daily needs, right?
Sam: Yes. They combined the gram amounts eaten with nutrient lists from food composition tables—databases listing vitamins and minerals per bite of common foods from nearby countries like Peru. They divided each nutrient's intake by the Estimated Average Requirement, or EAR—the amount that covers needs for half the population. A ratio near or above one means likely meeting needs. Then they averaged those ratios across nutrients to get one overall diet quality number, called MAR.
Alex: So MAR blends coverage across nutrients. With messy real-world data, how'd they handle gaps?
Sam: For women absent at one visit, they used a filling method that predicts missing intakes based on patterns in everyone else's data, averaging multiple guesses for reliability. Since nutrient data was bunched up rather than evenly spread, they reported medians and used non-parametric tests to compare against EARs safely.
Alex: That cleanup let them trust the links. So more local species richness meant higher MAR?
Sam: The analysis confirms traditional foods supplied about 39 percent of energy and raised MAR. Each additional local species linked to a 0.033 rise in median MAR for macronutrients and 0.052 for micronutrients—both statistically solid. Models adjusted for age, education, jobs, and village.
Alex: Models adjusted for those factors... what kind of analysis nailed down that link?
Sam: They used a tool that looks at the middle value of the scores—half above, half below—and sees if species count shifts it up, treating villages as groups that vary naturally. It confirmed each extra total species raised the median MAR notably, and the same for local ones.
Alex: Beyond MAR, they looked at diversity across food groups too?
Sam: Yes. They grouped foods into ten categories—like grains, veggies, proteins—and counted how many a woman hit. These women averaged six, above the threshold of five for solid micronutrient coverage, with local traditional foods filling key slots. But medians came in under 100 grams for fruits and even lower for vegetables, compared to 200 grams each recommended. Ruminant meat—like beef from cows—provided the top local energy source, but medians exceeded 60 grams daily, above the 50-gram cap suggested to limit greenhouse gases.
Alex: Over on meat for the planet, short on greens. So what are the real-world takeaways, and any caveats?
Sam: The evidence points to traditional foods meaningfully aiding micronutrient adequacy, with positive ties to overall diet quality. Promoting cultivation of fruits and vegetables—especially leafy ones—in home gardens could balance diets toward sustainability and reduce hidden hunger. Limitations include relying on food composition tables from Peru and Central America, not Ecuador-specific; data only from the rainy season; and no direct lab sampling of animal foods.
Alex: Fair points—those could tweak nutrient estimates or miss seasonal shifts. Overall, it seems like a solid case for building on local biodiversity.
Sam: Precisely. This study advances understanding of how rural diets can leverage what's on hand for better health. Thanks for listening to ResearchPod.