In 2013, the Silicon Valley Registered Dietitian Nutritionist’s Book Club gathered to discuss The China Study, by T. Colin Campbell. Originally published in 2005, the book continues to be discussed among consumers and health professionals. 

Here are some of the main ideas in the book:

• Chinese villages that consumed the least amount of animal protein had less cancer than the villages that consumed more animal protein.
• Consumption of casein (a protein found in milk) promotes cancer in rats.
• Nutrition must be considered holistically: “nutrition represents the combined activities of countless food substances. The whole is greater than the sum of its parts.”
• The How to Eat section of the book recommends a vegan eating pattern.

Areas of Agreement

Our group strongly agreed with a few principles in the book: eating more whole and minimally processed foods and plant-based foods like fruits, vegetables and beans will improve the health of most Americans. We also agreed that nutrients can’t be looked at in isolation, that the overall pattern of food choices and diets over time are what matter.

Where We Differ

Club members observed many holes in Campbell’s arguments. Here are just a few:

• The China Study is an observational study; in other words, it only identifies relationships between different variables. It does not prove that particular behaviors or food choices cause certain health outcomes. In the study, many other variables were overlooked that could increase cancer risk—such as industrialization, exposure to chemicals, and sugar and refined carbohydrate consumption. These could easily have been the culprits responsible for differences in cancer risk among groups.
• Although individuals in the counties studied may have been vegan, whole counties did not follow vegan food patterns, so it is difficult to understand how Campbell came up with his conclusions that all animal products should be omitted.
• Campbell’s experiments with casein were conducted with laboratory rats and mice. His hypothesis that casein behaves the same way in a whole food as when fed in isolation is flawed and violates his own philosophy to look at diets holistically. 
• Campbell is very selective in building his bibliography. A more comprehensive review of the literature reveals scientific research confirming the many health benefits that milk and dairy foods provide. For this reason, the Dietary Guidelines for Americans recommends that Americans consume two to three servings of milk and dairy foods per day.
• A long-term study conducted in Taiwan and published in 2014 found that increased dairy consumption meant lower risks of mortality from cardiovascular disease, especially stroke, but found no significant association with the risk of cancer.

Perhaps one of the most significant flaws of the book is that the recommendations are so extreme. Diets that remove entire food groups have the potential for unintended consequences of underconsuming essential nutrients. Bringing food choices into better alignment with the Dietary Guidelines is a preferred approach—specifically eating more underconsumed foods such as vegetables, fruits, low-fat dairy products, whole grains, beans, lean meats and fish while also reducing the consumption of refined grains, fats and sugars. These changes will go a long way toward promoting health.

Bottom Line

While we found this book interesting, our club members are sticking with a more balanced approach to nutrition and cannot recommend The China Study. We equipped each other with talking points to use when someone—friend, neighbor, relative, client or colleague—asks questions about The China Study. It is important for consumers to understand the basis for Campbell’s flawed conclusions and the potential negative consequences of following diets that omit whole food groups.

References

Huang LY, Wahlqvist ML, Huang YC, Lee MS. Optimal dairy intake is predicated on total, cardiovascular, and stroke mortalities in a Taiwanese cohort. J Am Coll Nutr. 2014;6:426-436. doi:10.1080/07315724.2013.875328