MAPPED: The companies under siege by the Whole Foods-Amazon merger (WFM, SFM, WMT, KR)

The deal has caused some investors to speculate about which companies will see their business suffer the most.

It was at least partially responsible for Blue Apron having to lower its IPO price. Additionally, competitors in the grocery and pharmacy fields have seen their shares fall significantly over the last week.

Morgan Stanley took a novel approach to analyzing the deal, in a recent note to clients. The investment bank mapped Whole Foods locations across the nation. It then used that map to compare those store locations to the competition.

The results showed that there is a Whole Foods store with five miles of 54% of Sprouts Food Market stores, 31% of Kroger stores and 12% of Walmart stores. Morgan Stanley argues that the companies with more stores near a Whole Foods will see the biggest negative impact from the Amazon deal.

"Retailers with greater Whole Foods overlap could be most at risk for incremental top line pressure," Morgan Stanley wrote. "More broadly, we see a setup for industrywide margin pressure, with a combination of increasing price competition and a greater need to invest in omni-channel capabilities."

Morgan Stanley found that in a 10-mile radius from its approximately 450 stores, Whole Food reaches 144 million customers. Kroger, in comparison, reaches 155 million customers but has about 2,800 stores. Costco reaches 172 million with about 500 stores.

That means the average Whole Foods store reaches 478% more Americans than the average Kroger store. Impressive.

Because of the Amazon deal, investors are bearish on a lot of Whole Foods' competitors. "Food retail stocks are generally pricing in no earnings growth, which we believe is fair," Morgan Stanley said.

Target will probably be hit the hardest by the Amazon deal, according to Morgan Stanley. The company has previously struggled in the grocery category and has one of the highest location overlaps with Whole Foods.

Amazon is up 29.2% this year and is trading at $974.57 a share.