in west africa small children often exist on a diet of rice and palm oil, meat is usually reserved for adults.
I saw children as young as 6 years old hunting birds and insects.
where I was living in west africa they grow dryland rice actually a red rice with a wonderful aroma. Other than clearing the land, women do most of the work. Typically every evening you would see women with a large bowl balanced on their heads with rice stalks returning home from their fields. I was always interested in buying their rice whenever it was in the market. Throughout the day walking around town I would see women pounding the rice in large wooden mortars to remove the hull. Fortunately the processing is imperfect so I think they still get some benefit from the remaining hull.
The only imported rice was very old polished rice from usaid. The locals were quite aware of its inferiority.
Yes, I know of places where 80-90% of the diet is rice and a variety like this might offer significant health benefits (assuming it could be grown without purchased inputs, which they can't afford). But I suspect that it would be culturally unacceptable to many. People expect their food to look a certain way, and subsistence farmers tend to be very conservative. Efforts to get people to use solar ovens rather than charcoal, for example, don't work because the former are seen as unfamiliar and weird. (They also can't always be made with local materials, reinforcing dependency, an issue that's also a major problem for most GE crops, golden rice excepted.)