Boron, lithium and silicon roles in health reviewed
What it found
Human evidence on boron, lithium and silicon is still limited, coming mostly from small trials and observational studies.
The authors say it is not enough to set dietary recommendations or support supplements.
What they found
Studies in people
Boron and hormones
Human studies found boron raised levels of active testosterone and estradiol by lowering a binding protein called SHBG. It may also affect thyroid hormones, but the authors say more studies are needed.
Boron and thinking skills
Older, small human trials linked low boron intake to changes in brain wave patterns and slightly worse attention, short-term memory and movement speed. The authors say these studies used dated methods and had too few people to be confident.
Studies in people and animals
Boron and inflammation
Boron was found to lower several inflammatory signals, including NF-kB, COX-2, IL-6 and TNF-alpha. The authors say the human trials behind this had small numbers of participants.
Boron and bone minerals
Boron helps activate vitamin D and increases magnesium retention, which supports calcium use in bone. The authors describe these effects as supporting bone health.
Boron safety limits
The European Food Safety Authority sets an upper limit of 10 mg per day for adults, and the World Health Organization suggests 10 to 20 mg per day. Taking more than 20 mg per day for a long time may cause mild stomach upset and skin irritation, and animal studies found reproductive harm at very high doses.
Lithium and silicon
Lithium studies were mostly ecological, linking higher water levels to lower suicide rates, which cannot show cause. Silicon studies were mostly observational and looked at bone health, with some evidence on gut barrier function.
What the authors conclude
“Although Li-Si-B display compelling mechanistic potential, current human data are insufficient to justify dietary recommendations or supplementation.”
Also in their conclusions
- They say current human data are insufficient to justify dietary recommendations or supplementation for lithium, silicon or boron.
- They call for standardized exposure databases, large dose-response human trials, clarified upper limits and more research on how these elements interact.
- They advise that systematic monitoring of trace element levels in water is more appropriate than changing water composition at this time.
How it was done
The authors wanted to pull together what is known about how these three trace elements affect metabolism, the brain, bones and gut bacteria, and to point out where research is missing.
They searched three scientific databases up to January 2025 and included 79 peer-reviewed studies in people, animals or cells. They left out studies using drug-level lithium doses or industrial forms of silicon.
What it can’t tell you
- Most human studies on boron were small and had inconsistent methods, so the results may not apply to everyone.
- Ecological studies on lithium cannot show that lithium itself caused the health effects seen.
- The idea that these three elements work together is a hypothesis and has not been tested directly.
Who paid
- Conflicts
- The authors declare no conflicts of interest.
- Authors work at
- International Hellenic University, Greece; Private Nutrition and Dietetics Center, Greece; University of Milano-Bicocca, Italy
The paper
- Title
- Dietary Lithium, Silicon, and Boron: An Updated Critical Review of Their Roles in Metabolic Regulation, Neurobiology, Bone Health, and the Gut Microbiome
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Melenikioti E, Pavlidou E, Dakanalis A, Giaginis C, Papadopoulou SK (2026). Dietary Lithium, Silicon, and Boron: An Updated Critical Review of Their Roles in Metabolic Regulation, Neurobiology, Bone Health, and the Gut Microbiome. Nutrients. doi:10.3390/nu18030386Free full textPubMed 41683210DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error