A growing mistrust of artificial ingredients is prompting major companies to overhaul how they make food and drinks, and experts say the trend isn't going away any time soon.

Earlier this week, Pepsico announced Diet Pepsi will no longer contain the sweetener aspartame. The move follows Kraft's decision earlier this year to change the artificial coloring used in its popular Mac & Cheese and Nestle's decision to remove artificial flavors and colors from candies.

Chipotle also announced recently the completion of its two-year effort to remove genetically modified organisms from its food supply.

"Consumers aren't content with the dirty labels, the complicated and chemically sounding ingredients," said Billy Roberts, senior research analyst for food and drink at the research firm Mintel.

Thanks to smartphones, consumers can easily look up information on a product before purchasing it, making them "much savvier than they ever have been," Roberts said.

In an upcoming survey, Mintel found that 39 percent of all consumers look for GMO-free foods when they shop. The trend appears to skew younger, with 52 percent of millennials seeking non-GMO foods compared to only 28 percent of baby boomers.

The survey was of 2,000 people ages 18 and older.

Consumers' increasing anxiety about what is in their food, especially GMOs and artificial ingredients, appears unsupported by evidence. There is no evidence of safety or health problems related to GMOs.

Chipotle is a bit of an outlier as the company's brand is built on "food with integrity," promoting use of grass-fed beef and locally-sourced ingredients.

The rest of the moves can be chalked up to consumer pressure, nutrition and diet expert Marion Nestle told the Washington Examiner.

"They are responding to what they perceive as customer preferences and attempting to reverse declines in sales," said Nestle, a professor at New York University.

That is especially true of Pepsico, which saw sales of Diet Pepsi decline by 5 percent last year, according to trade magazine Beverage Digest.

Diet Pepsi will now be sweetened through sucralose and acesulfame potassium. Pepsi's main rival Coke has said it will not change its sweetener from aspartame.

The sweetener hasn't been linked to any health problems, but deep mistrust of aspartame lingers for consumers.

So far it doesn't appear that Congress is going to step in to put more regulations on GMOs and other products. Advocates have called for labeling of products made from GMOs, but the Food and Drug Administration has only released voluntary advice for manufacturers to do so.

Nestle believes that the trend of removing unpopular artificial ingredients is only just beginning.

"If the pressure [from consumers] stays up, others will have to follow," she said.