Alibaba starts taking the lead in China, simply enough, by connecting big Chinese manufacturers (制造商) with big buyers across the world. Its business-to-business site, Alibaba.com allows business to buy almost everything. Alibaba’s advantage isn’t hard to identify: size. Alibaba is just big, even by Chinese standards. Its marketplaces attract 231 million active buyers, 8 million sellers, 11.3 billion orders a year — and Alibaba is just the middleman. It encourages people to use its markets — not charging small sellers a percentage of the sale.

If you want a quick look into the influence of Alibaba on daily Chinese life, take my experience. I moved to Beijing almost a year ago and quickly got tired of visiting small stores across the crowded, polluted city of 20 million people in search of new electronics, bathroom furnishings, and anything else my wife wanted. “You’re looking for what exactly? Why not try it?” my Chinese teacher asked me one day. With that, my wonderful new relationship with Alibaba began.

Alibaba’s original business-to-business model now is second to consumer buying. Chinese retail (零售) buying makes up 80% of Alibaba’s profit, and leading that group is Taobao, with 800 million items for sale and the most unbelievable selection of things you’ll ever find. TMall.com is Alibaba’s other big site, where you can find brand name goods from Nike and Unilever near the lowest prices. What I have a hard time explaining to friends and family back in the U.S. is how China has gone beyond traditional shopping — big-box retailers especially — in favor of online purchases on Taobao and a few other sites. In smaller towns than Beijing, where big retailers have not yet traveled, shopping online is shopping, and shopping is Taobao.

I have a list of some of my recent purchases on Taobao for a sense of how wide the marketplace is. Almost everything arrived a day or two after ordering with free shipping. I’m not even a big buyer, because I need friends to help me search the Chinese-language site. When I was searching my purchase history on my Chinese teacher’s iPad, which helps me buy goods, I looked through with great difficulty about 10 of her purchases for every one of mine.

Visit the grocery store on an empty stomach, and you will probably come home with a few things you had not planned to buy. But hunger is not the only culprit behind such purchases. The location of store displays also influences our shopping and may make or break some healthy eating habits.

The checkout area is a particular hotspot for junk food. Studies have found that the products most commonly found there are sugary and salty snacks-and a few studies have suggested that simply swapping in healthier options can shift customer behavior. A 2012 study in the Netherlands found that hospital workers were more likely to give up junk food for healthy snacks when the latter were more readily available on canteen shelves, for example, In 2014 Norwegain and Icelandic researcher likewise found that replacing unhealthy items with healthy ones in the checkout area significantly increased last-minutes sales of healthier foods.

These findings caught the attention of the New York City Department of Health and Mental Hygiene, which has been working with more than 1,000 store owners to encourage them to stock and promote consumption,” says Tamar Adjoian, a research scientist at the department. “Making healthy food more convenient or appealing can lead to increased sales of those products.”

Adjoian and her colleagues wondered if such findings would apply to their city’s dense urban checkout areas, so they recruited three Bronx supermarkets for their own study. They gave one checkout line in each store a healthy makeover, replacing candy, cookies and other processed snacks with fruit , nuts and similar items containing 200 or fewer calories per serving. Then they recorded purchases over six three-hour periods in each store for two weeks.

Of the more than 2,100 shoppers they observed, just 4 precent bought anything from the checkout area. Among those who did, however, customers in the healthy lines purchased nutritious items more than twice as often as those in the standard lines –and they bought unhealthy items 40 percent less often. The findings were reported in September in the Journal of Nutrition Education and Behavior.

The potential impact may seem small, but Adjoian believes that converting more checkout lines would open customers’ eyes to nutritious, lower-calories foods. Health department officials are now exploring ways to expand healthy options at checkout areas throughout New York City.