"The airline cycle is alive and well," Jim Cramer told a caller who asked about Boeing (BA) - Get Report on his "RealMoney" radio show Friday.

Cramer predicted Boeing, which has dropped from $86 to $72, will make a stand at $70. That's the level to buy it at, but not before then, Cramer said.

He told the next caller he considers

Aetna

(AET)

worst of breed, as the company keeps missing its estimates.

On the other hand,

UnitedHealth Group

(UNH) - Get Report

, which Cramer owns for his charitable trust,

Action Alerts PLUS, and is selling at one times its growth rate, "is the way to play this group," he said.

Although UnitedHealth's CEO is in the middle of a backdating scandal, Cramer believes the CEO "will be vindicated."

"I would sell Aetna very hard here because it's going from $36 to $30," he predicted.

Responding to his next caller, Cramer said he "likes

Ecolab

(ECL) - Get Report

very much," as the company provides services, such as pesticide control, that people pay for regardless of the economic situation.

He advised anther caller to stay away from

Gemstar

(GMST)

, calling it "a serial disappointer."

When a listener called in from Taiwan inquiring about

Chesapeake Energy

(CHK) - Get Report

, Cramer said "no one cares that

natural gas stocks are cheap," even though he, himself, owns some natural gas for his charitable trust.

"I have trimmed back my oil holdings but I don't want to give up everything, because the world is a dangerous place and oil a good hedge against that danger," he said.

However, Cramer said he doesn't want to own Chesapeake right now, as he doesn't see a bottom in the group. He said "oil is in free fall" and compared it to "falling knives." Instead, Cramer said he prefers food and beverage stocks, financials and tech stocks more.

To see the most recent edition of The RealMoney Radio Recap in its entirety, please click here. This recap is published every day around 3 p.m. ET.

At the time of publication, Cramer was long UnitedHealth Group.

Jim Cramer is a director and co-founder of TheStreet.com. He contributes daily market commentary for TheStreet.com's sites and serves as an adviser to the company's CEO. Outside contributing columnists for TheStreet.com and RealMoney.com, including Cramer, may, from time to time, write about stocks in which they have a position. In such cases, appropriate disclosure is made. To see his personal portfolio and find out what trades Cramer will make before he makes them, sign up for

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