US supplement study shows boost in immunity, gut health & anti-inflammatory products

A study has evaluated the US trends in nutritional supplements over 24 years and found that multivitamin-multimineral (MVMM) use has seen a decline, while supplements marketed for immune, gut, joint, and skin health, and anti-inflammatory claims, have increased. 

Between the years 1999–2000 and 2021–2023, the overall supplement use increased from 51% to 60%, with the most growth observed after 2010.

The study authors note that the COVID-19 pandemic may have impacted these results, as supplement use was influenced, especially for immune health. There was also a global increase in demand and sales of supplements during this period. However, its impact on the US population is still unclear, they add.

The paper also stresses that evidence supporting supplements’ impact on health remains mixed, as some findings show benefits while others indicate potential harm.

“For example, evidence is insufficient to support routine single-vitamin or multivitamin use for preventing cardiovascular disease or cancer. In addition, evidence on adverse interactions between supplements and medications remains limited for many products despite the large and growing supplement marketplace,” reads the study.

It states that despite rising public interest, no comprehensive review has evaluated emerging trends, particularly for botanicals and other nonvitamin nonmineral supplements.

“Therefore, this study examined more than two decades of National Health and Nutrition Examination Survey data to characterize national trends in supplement use, with particular attention to evolving product categories, temporal pattern changes over time, sociodemographic subgroups, and periods surrounding the COVID-19 period,” write the authors.

Overall upward trend

The paper, published in JAMA Network Open, includes data from 63,442 adults. The participants were asked about their dietary supplement consumption over the past 30 days during house visits or phone calls.

The researchers saw a stable trend in supplement use before 2009–2010, followed by an increase.The study found that 51% reported using any type of supplement between 1999–2000 and 60% in 2021–2023.

The research team also looked into using four supplements or more, where they observed a similar trend, as 8.8% reported this in 1999–2000 versus 15% in 2021–2023. 

For both groups, those consuming any supplement or those consuming four or more, the researchers saw a stable trend before 2009–2010, followed by an increase in use. 

“Notably, the largest absolute increases in supplement use were observed among adults aged 65 years or older (from 62% to 78%), followed by those with less than a high school education (from 33% to 48%), and Mexican American individuals (from 32% to 49%),” the study details.

Trending vitamins and minerals

The research team also looked more closely at vitamin and mineral use over the years. Vitamin use increased from 47% to 54%, while no significant differences were observed for long-term mineral use. 

When MVMM use was excluded, vitamin use increased from 25% to 39%, and mineral use increased from 18% to 27%.

When looking at social demographics, there were also changes observed between groups. Older adults were consuming more vitamins and minerals, while younger and middle-aged adults used vitamins, including MVMM. Additionally, Mexican-American adults had an increase in vitamin use, but not in minerals. 

Vitamin D use increased from 5.1% to 29%, and zinc use increased from 4.6% to 11%. The researchers also saw notable increases in vitamin K, biotin, vitamin B12, potassium, copper, iron, and magnesium use.

Vitamin D use increased from 5.1% to 29%, and zinc use increased from 4.6% to 11%.They also found decreases in the use of nickel, silicon, tin, vanadium, chromium, and boron. 

Additionally, the study did not find a significant trend for botanical supplements, although joinpoint analyses indicated a modest decline between 2009 and 2010, followed by a growth in recent years.

Turmeric, curcumin, lycopene, and omega-3 saw increased use over time. Other supplements that showed an emerging pattern include açai, ashwagandha, hyaluronic acid, collagen, elderberry, prebiotics, and probiotics. 

Ginseng, ginkgo, gotu kola, carnitine, ephedra, hesperidin, para-aminobenzoic acid, lecithin, and garlic showed overall decreases in use.

“Emerging trends in supplements marketed for immune, adaptogenic, or anti-inflammatory support, such as zinc, elderberry, ashwagandha, and turmeric and curcumin, were apparent both over long-term and between the prepandemic and early-pandemic and later-pandemic and postpandemic periods, consistent with prior reports documenting increased immune-related supplement use during COVID-19,” reads the paper.

Study limitations

The authors also note certain limitations, including measuring supplement use over the past 30 days, not taking seasonality into account, and not including dose frequency, as the study focused on overall trends. 

“Moreover, the supplement marketplace changed substantially over the study period; changes in product availability and marketing, and classification of products as dietary supplements versus foods or beverages may have influenced reported use across survey cycles and, therefore, affected interpretation of temporal trends,” reads the study.

Additionally, the research took place before, during, and after the COVID-19 pandemic, which may have impacted the results, causing changes in trend patterns and increasing the demand for immune-supporting supplements.