Background: The National Nutrition Research Roadmap has called for support of greater collaborative, interdisciplinary research for multiple areas of nutrition research. However, a substantial reduction in federal funding makes responding to these calls challenging.

Objectives: The objectives of this study were to examine temporal trends in research funding and to discuss the potential consequences of these trends.

Methods: We searched the NIH RePORTER database to identify NIH research grants and USASpending to identify National Science Foundation and USDA research grants awarded from 1992 to 2015. We focused on those that pertained to vitamin research. For the years 2000 to 2015, we examined funding trends for different vitamins, including vitamins A, B (one-carbon B-vitamins were considered separately from other B-vitamins), C, D, E, and K.

Results: From 1992 to 2015, total federal research spending increased from ;$14 to $45 billion (2016 US dollars). Although vitamin research spending increased from ;$89 to $95 million, the proportion of grants awarded for vitamin research declined by more than two-thirds, from 0.65% in 1992 to 0.2% in 2015. Federal agencies awarded 6035 vitamin research grants over the time period, with vitamin A associated with the most research projects per year on average (n = 115) and vitamin K the fewest (n = 8). Vitamin D research projects were associated with the greatest average yearly project value ($34.8 million).

Conclusions: Vitamin research has faced a disproportionate decline in research funding from 1992 to 2015. Insufficient federal research funding streams risk stalling progress in vitamin research and leaving important advancements unrealized.