Is this a proverb: "Food comes first for the people"?
Here's the prargraph from the book:

“Food comes first for the people,” says an ancient Chinese proverb, and foodie culture has blossomed in China as hedonism has grown less stigmatized. The average Chinese citizen spent more money on food in 2015 than at any time in the past, and food TV shows such as A Bite of China have soaring ratings. Nearly two-thirds of Chinese mobile-phone users consistently photograph their food before eating, then share these photos through food-oriented apps and social media; fluency in food culture is deemed a mark of sophistication. The China Cuisine Association has asked UNESCO to place the country’s cuisine on the Intangible Cultural Heritage List. Demand for premium and organic foods keeps increasing. Recent research has found that people who eat spicy food all the time live substantially longer; though the exact causality is unclear, the study has been warmly received. Torrents of fabulous new restaurants have opened for wealthy Chinese and Westerners; in Shanghai alone, five recently made the list of Asia’s Best Restaurants.

Obviously referring to this real proverb:
民以食为天
It is a very well-known, common proverb or idiom; verbatim search on Google, alone, gives:

1,120,000 results

and Baidu gives:

12,000,000 results

ABC defines it as:

The masses regard food as their prime want.

and CC-CEDICT defines it as:

Food is the God of the people. (idiom); People view food as the primary need.
Food first, ethical niceties second


There's a whole question about it over here:
What does 民以食为天 mean?
@Huang's answer is also a good source for more information:
https://chinese.stackexchange.com/a/630/4136

ABC Proverbs also has the following:
国以民为本；民以食为天。

Lit  A country depends on [its] people as [its] base, [just as] the people depend on food [to survive].


Other examples of this usage:
english4tw's artle:  Hsinchu City God Temple, where food comes first for the people/新竹城隍廟:民以食為天

There is a saying in the Chinese-speaking community, &quot;Food comes first for the people&quot;;
華人社會常說，民以食為天;

labbrand's article China’s Digital Powered Foodie Revolution

Through the best of times and the worst of times, food is always on the mind of Chinese people. As a famous Chinese proverb goes, “Food comes first for the people” (民以食为天). Today, Chinese people’s relationship to food and food products is changing. Every week new trends and behaviors emerge that present new challenges but also new opportunities for brands in the F&amp;B industry. In this article, we look at how digital channels have changed the way modern Chinese consumers purchase and use food products along with how food has become one of the most important elements of contemporary Chinese pop culture.