ROCKVILLE, Md. — Shifting household dynamics are changing the way Americans shop for groceries. Most notably is the diversification of the primary store shopper with moms no longer always assuming this role exclusively, according to market research firm Packaged Facts in the recently released report, Retail Food Marketing Trends in the U.S.: Technology, Mobile& Social Media.

“Mom isn’t the only shopper for household groceries anymore. There’s a significant constituent of men who identify as primary shoppers themselves, regardless of whether they share or wholly fulfill grocery shopping responsibilities,” said David Sprinkle, research director for Packaged Facts, Rockville, Md. “There’s evidence that the percentage of men who are now the primary shoppers in their households has more than doubled in the past two decades.”

Research shows that men clearly shop differently than women. Overall, men tend to shop with greater weekly frequency and spend less time in the store.

The good news for retailers is that men tend to spend more, yet purchase fewer items—making their average cost per item higher. This suggests that women may still do the “big” grocery shopping trips for their household, while men are tasked with the intermitent grocery store trips to pick up staples or food for immediate use (such as meat or vegetables for dinner that night).

Food marketers must be aware that age/generation also plays a role in shopping behavior, however, and shifts in gender household responsibility are evident in grocery shopping behavior by both age and generation. Younger males are the most likely to be involved in frequent shopping trips as those aged 18-34 (i.e., Millennials) are 161% more likely than average to shop four or more times per week. In contrast, men aged 55 and older significantly under index in shopping as often. At best, older men will shop once a week for items.

Millennial dads in particular are proving to be a very unique group, with behaviors that are a significant departure from previous generations. This set had a different upbringing and don’t subscribe to traditional gender norms. Because of this, millennial dads are redefining fatherhood by spending more time with their kids, doing a larger portion of the household shopping and spending lots of money.

This shift is evident in grocery shopping trip behavior. While younger men are certainly shopping more than their older counterparts, being a parent is a key driver in their likelihood to grocery shop. Millennial dads are significantly more likely to shop more than four times a week when compared to the average shopper. Notably, these dads aren’t just making the quick shopping trips as they over-index in shopping for more than an hour. The value of this demographic is elevated when considering their higher average spending ($170 compared to $108 of all) and increased cost per item. The implication is that millennial dads are likely seeking out quality over a good deal.