InTeGrate Modules and Courses >Future of Food > Student Materials > Module 3: Diet and Nutrition > Module 3.2: Food System Issues for Nutrition > Case Study: Lactose Tolerance
InTeGrate's Earth-focused Modules and Courses for the Undergraduate Classroom
showLearn More
These materials are part of a collection of classroom-tested modules and courses developed by InTeGrate. The materials engage students in understanding the earth system as it intertwines with key societal issues. The collection is freely available and ready to be adapted by undergraduate educators across a range of courses including: general education or majors courses in Earth-focused disciplines such as geoscience or environmental science, social science, engineering, and other sciences, as well as courses for interdisciplinary programs.
Explore the Collection »
show Download
The student materials are available for offline viewing below. Downloadable versions of the instructor materials are available from this location on the instructor materials pages. Learn more about using the different versions of InTeGrate materials »

Download a PDF of all web pages for the student materials

Download a zip file that includes all the web pages and downloadable files from the student materials

For the Instructor

These student materials complement the Future of Food Instructor Materials. If you would like your students to have access to the student materials, we suggest you either point them at the Student Version which omits the framing pages with information designed for faculty (and this box). Or you can download these pages in several formats that you can include in your course website or local Learning Managment System. Learn more about using, modifying, and sharing InTeGrate teaching materials.

Case Study: Lactose Tolerance

We have already mentioned that some humans are lactose tolerant and others are not. Specifically, humans from ethnic groups that did not traditionally consume dairy, such as Native Americans, East Asians, and some Africans, are usually lactose intolerant. In the US, science recognized early on that pregnant women need extra calcium, and also that milk is an excellent source of calcium. Therefore, doctors until recently would recommendation increased milk consumption to all pregnant women patients. Unfortunately, it took time for nutritionists and the medical profession to realize that this advice is not beneficial to women who are lactose intolerant, such as most Asian-Americans, Native Americans, and many African-Americans. Of course, calcium is an essential mineral, and so the members of these ethnic groups did include excellent sources of calcium in their diets. For instance, West African diet typically includes enormous diversity and quantity of edible greens, which tend to be high in calcium. East Asians have tofu, and bone broth used to make soup. How many US doctors even today know to advise pregnant African-Americans to increase their consumption of greens, rather than milk? Even in China now, the government is actively promoting milk consumption, apparently unaware of the problems associated with lactose intolerance.

This example illustrates that humans vary in their ability to digest foods. It is quite possible, for instance, that West Africans may be able to digest leafy greens better than most other humans, and that East Asians may be less affected by the high levels of estrogen-like compounds in soy products than others as a result of their long history of soy consumption.<


These materials are part of a collection of classroom-tested modules and courses developed by InTeGrate. The materials engage students in understanding the earth system as it intertwines with key societal issues. The collection is freely available and ready to be adapted by undergraduate educators across a range of courses including: general education or majors courses in Earth-focused disciplines such as geoscience or environmental science, social science, engineering, and other sciences, as well as courses for interdisciplinary programs.
Explore the Collection »