Table 1.
Class of agent | Agent | Current strength of association with IA or T1D | Proving contribution to causality | Supporting References |
---|---|---|---|---|
Infections and vaccinations | Enterovirus | Probable | Vaccination trials in planning | (48, 57) |
Rotavirus | Possible | Rotavirus vaccinations being incorporated into childhood vaccination programmes in some countries | (58, 65) | |
Influenza | Unlikely | Studies show inconsistent results | (70–73) | |
COVID-19 | Possible | Vaccination programmes being set up | (37, 75–78, 87) | |
Childhood vaccinations | Unlikely | Studies show inconsistent results | 91, 92 | |
Weight | Birthweight | Probable | RCT and intervention studies needed | (29, 111, 112) |
Infant growth | Probable | RCT and intervention studies needed |
113, 114
(192) |
|
Childhood obesity | Probable | RCT and intervention studies needed | (115–119) | |
The Gut | Microbiome | Probable | RCT needed | (31, 129, 131–133) |
Breastfeeding | Possible | RCT evidence supports no role | (131, 151) | |
Cow’s milk/formula feeds | Unlikely | RCT evidence supports no role | (32, 33, 153, 155) | |
Gluten | Possible | Studies show inconsistent results | (156, 159–161) | |
Antibiotic use | Possible | Studies show inconsistent results | (166, 168–170) | |
Probiotic use | Possible | RCT evidence supports no role but small study | (150, 172) | |
Vitamin D | Possible | Conflicting RCT results of vitamin D supplementation | (176–178, 182–184) | |
Nicotinamide | Unlikely | RCT evidence supports no role | (34, 35) | |
Omega-3 (PUFA) | Possible | Conflicting RCT results of PUFA supplementation | (188, 189) |