Kim Kardashian has joined Tinseltown's struggle to nurture Mother Nature, and she and her NFL beau Reggie Bush are making a super-steamy contribution to conservation.

"I conserve water by showering with my boyfriend so we can save water together," Kardashian told Tarts this week at Svedka Vodka's launch of their eco-friendly T-shirt collection E.VIL to benefit Heal the Bay, held at Fred Segal in Santa Monica, Calif.

Video: Kim and Reggie Get Wet n' Wild

But does showering with your loved one save or actually waste water?

The Department of the Interior, U.S. Geological Survey & Water Science for Schools found that the average American uses two gallons of water per minute while showering, so obviously cutting that in half is helpful. But some experts argue that sharing the faucet with someone you're pretty fond of could lead to activities that prolong the time spent in the shower, therefore doing even more damage.

But getting wet and wild in the bathroom isn't the only effort Kimmy makes to be eco-friendly.

"Oh, I've also changed my light bulbs," she said. "I definitely have energy-saving light bulbs now."

Speaking of the reality-television sexpot, it turns out she's been on a dinner date with a high-profile politician that isn't (her) Mr. Bush.

Kim revealed to an E! reporter earlier this week that she once dined with Democratic candidate Barack Obama.

"I had dinner with him [Obama] once, and he just seemed very firm about the change, and that's his motto," Kardashian said, referring to the slogan "Change We Can Believe In."

Alessandra Ambrosio Heartbroken; Plus, Is She Having a Girl?

To the world she has "wings," but it seems as though things aren't flying so high in the personal life of Victoria's Secret "Angel" Alessandra Ambrosio.

According to a source very close to the leggy lingerie lass and her trust-fund beau Jamie Mazur, his failure to propose is causing strain on the relationship.

"Alessandra really wants the ring and feels uncomfortable being five months pregnant and not married," our source said. "She gets really upset when people ask about it and it's stressing her and the relationship out big-time."

Our insider added that Jamie's Jewish background compared to Alessandra's Polish/Italian inheritance could be what's holding up the proposal.

"They are both in love, that isn't in question," the insider said. "We're hoping he will propose after the baby is born."

Pop Tarts has been told that Brazilian-born Ambrosio is expecting another little "Angel" come August. Apparently, the sexy model has told friends that she is having a girl and was even spotted wearing a silver necklace saying "it's a girl" at a recent party in the Hollywood Hills. Awww.

Calls to Ambrosio's rep were not returned.

Carrie Underwood: 'Obsessive Compulsive' About Food?

We've watched Carrie Underwood shrink considerably since her Season 4 win of "American Idol," but while most stars blame their weight-loss on being "busy," Carrie is honest about her calorie-counting obsession.

"I think about what I look like probably more than I should. But I think everybody is their own worst critic," the country crooner revealed in the May issue of InStyle, adding that she always keeps a food diary and is "OCD like that."

"I count calories, fat and fiber — which is important in making you feel fuller faster — and protein, especially when I'm working out," she added. "If I put on five pounds, it's noticed immediately."

But body image isn't the only hardship Carrie has experienced. The "Before He Cheats" singer has had to learn to "let go and move on" from unfaithful boyfriends.

"I've been cheated on a time or two. It's tough," the former flame of Tony Romo and Chace Crawford added.

Jim Carrey Extinguished by Fire Marshals

Even being one of Hollywood's hottest doesn't guarantee you entry into one of Hollywood's hottest parties.

High-profile couture designer Lloyd Klein hosted a smokin' soiree at his Los Angeles boutique on Friday evening, which drew such a crowd (and had so much candlelight) that the Los Angeles Fire Department called in more than 30 firefighters, two helicopters and several cops to "put out" the party.

However, the likes of Stacy Keibler and British socialite Lady Victoria Hervey (who threw a prominent hissy fit) weren't the only celebs who were denied entry into the exclusive bash. We're told Jim Carrey and his stylist were also rejected, and apparently they even waited around for a good 20 minutes to get inside before being ordered off the premises. Ouch.

"The firemen were rude but still found time to stare at the scantily clad models," an event organizer said. "The fire marshal brought in an excessive amount of firefighters, which actually made it more imposing and unsafe. Traffic was backed up for a mile on Beverly Boulevard and guests were forced to wait hours to get their car from valet."

Ironically, Klein just recently donated $50,000 to the firefighter's fund — adding to his anger that the brigade put such a prompt stop to his swanky bash.

"My next party will be a Firefighter's Ball," he spat back after fire officials sent all his attendees home.

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