Background
Methods
Subjects, settings and procedures
Statistical analysis
Results
Sample
Prevalence and characteristics of NHP use
NHP | Males (n = 28) % (95% CI) | Females (n = 69) % (95% CI) | Total (n = 97) % (95% CI) | BCNS (n = 1823) % (95% CI) |
---|---|---|---|---|
Water Soluble Vitamins (Single)
| ||||
Vitamin B6 or pyridoxine | 68 (51 to 85)***
| 14 (6 to 23) | 31 (22 to 41) | 0a
|
Vitamin B9 or folic acid | 71 (55 to 88)***
| 28 (17 to 38) | 40 (30 to 51) | 0a
|
Vitamin C | 64 (47 to 82) | 67 (56 to 78) | 66 (56 to 75)+++
| 24 (22 to 26) |
Fat Soluble Vitamins (Single)
| ||||
Vitamin A | 25 (9 to 41)*
| 4 (0 to 9) | 10 (5 to 18)+++
| 2 (1 to 3) |
Vitamin D | 61 (43 to 79) | 51 (40 to 62) | 64 (54 to 79)+++
| 1 (0 to 2) |
Vitamin E | 46 (28 to 65) | 46 (35 to 58) | 47 (37 to 58)+++
| 17 (15 to 19) |
Vitamin Combinations
| ||||
Vitamin B complex (with or without vitamin C) | 68 (51 to 85) | 49 (37 to 61) | 55 (44 to 65)+++
| 9 (8 to 10) |
Vitamin A and D combination | 21 (6 to 37)*
| 4 (0 to 11) | 9 (4 to 17)++
| 3 (2 to 4) |
Multivitamins | 14 (1 to 27) | 19 (10 to 28) | 18 (11 to 27)+
| 9 (8 to 10) |
Minerals (Single and Combinations)
| ||||
Iron preparations | 21 (6 to 37) | 20 (11 to 30) | 34 (25 to 44)+++
| 1 (0 to 2) |
Singleb and multiple mineralsc
| 79 (63 to 94) | 78 (69 to 87) | 78 (69 to 86)+++
| 13 (11 to 15) |
Vitamin and Mineral Combinations
| ||||
Vitamins and minerals | 61 (43 to 79) | 59 (49 to 71) | 60 (49 to 70)+++
| 31 (29 to 33) |
Other NHPs
| ||||
Enzymes or gastrointestinal productse
| 46 (28 to 65) | 30 (20 to 41) | 35 (26 to 45)+++
| 6 (5 to 7)d
|
Replacementf or homeopathic preparationsg
| 46 (28 to 65) | 29 (18 to 37) | 34 (25 to 44)+++
| 5 (4 to 6) |
Herbal and natural productsh
| 61 (43 to 79) | 51 (39 to 63) | 54 (43 to 64)+++
| 19 (17 to 21) |
Other productsi
| 61 (43 to 79)*
| 88 (81 to 96) | 75 (65 to 83)+++
| 20 (18 to 22) |
NHPs and potential for adverse events
Vitamin/mineral | ULa
| % > ULa(95% CI) | LOAELb
| % > LOAELb(95% CI) | Effect at the LOAELb
|
---|---|---|---|---|---|
Vitamins and Minerals with ULs
a
and LOAELs
b
| |||||
Vitamin B3 or niacin - mg | 35c
| 28 (19 to 38) | 50 | 19 (11 to 28) | Vasodilation causing flushing of the skin |
Vitamin B6 or pyridoxine - mg | 100 | 8 (4 to 16) | -- | -- | -- |
Vitamin B9 or folate - mcg | 1000c
| 17 (10 to 25) | 5000 | 0% | Precipitate or exacerbate neuropathy in vitamin B12 deficient individuals |
Vitamin Dd – mcg and Vitamin Ed - mg | D: 100; E: 1000e
| 3 (1 to 9) | D: 50; E: 39,545 and 18,000f
| 0% | Vitamin D: Hypercalcemia. Vitamin E: Increased tendency to hemorrhage seen in rats |
Calcium - mg | 2500 | 6 (2 to 13) | 5000 | 0% | Hypercalcemia, renal insufficiency |
Iron - mg | 45 | 7 (3 to 14) | -- | -- | -- |
Magnesium - mg | 350c; g
| 6 (2 to 13) | 360 | 6 (2 to 13) | Diarrhea |
Zinc - mg | 40 mg | 6 (2 to 13) | -- | -- | -- |
Manganesed - mg | 11 mg | 8 (4 to 16) | -- | -- | -- |
Vitamins and Minerals (without ULs
a
and LOAELs
b
)
| |||||
Product names
|
% (95% CI)
|
Adverse Events Reported in the Literature
h
| |||
Pantothenic acid, vitamin B5, pantethine, pantothenol, or D-pantothenate and Potassiumi
| 37 (28 to 49) | Forms of pantothenic acid: Diarrhea seen with 10 to 20 grams/day of calcium D-pantothenate [28]. Case report of eosinophilic pleuropericardial effusion in an elderly woman taking 10 mg of biotin and 300 mg of pantothenic acid daily for two months [29]. Nausea and heartburn, have been reported with pantethine [30] | |||
Potassium: Supplementation of potassium only is generally prescribed to treat hypokalemia while preventing hyperkalemia and medication interactions. Mild effects include nausea, vomiting, abdominal discomfort, and diarrhea [28] |
NHP used in sample | Adverse events reported for that NHP in the literaturea
|
---|---|
Cranberry (Vaccinium macrocarpon) | More than one litre daily may cause kidney stones [31]. (Note: In this sample, cranberry pills were used and did not exceed this level) |
Dehydroepiandrosterone (DHEA) or 5-Dehydro-epiandrosterone (5-DHEA) | |
Devil’s Claw (Harpago-phytum procumbens) | |
Dong Quai (Angelica sinensis), Chinese angelica | In a cross-sectional survey (n = 1818), one case was identified as a potential significant interaction between dong quai and anticoagulant/antiplatelet agents [37] |
Echinacea (Echinacea angustifolia, Echinacea pallida, Echinacea purpurea) | |
Evening Primrose Oil (Oenothera biennis) | |
Feverfew (Tanacetum parthenium; syn. Chrysanthemum parthenium (L.) Pers., Pyrethrum parthenium Sm.)
| Gastrointestinal upset [42, 43], nervousness, insomnia [44], and possible allergic responses in those sensitive to chrysanthemums, daisies, or marigolds. Potential cross-reactivity with other members of the Compositae family [45]. In cross-sectional survey (n = 1818), two cases of potential clinically significant interactions with anticoagulant/antiplatelet agents identified [37]. |
Flaxseed (common flax, linseed, Linum usitatissimum) | |
Garlic (Allium sativum) | Breath and body odour, and allergic reactions [51]. Excess use associated with spontaneous epidural hematoma [52]. Potential reactions include bleeding and hypoglycemia (likely not clinically significant) [53]. In cross-sectional survey (n = 1818), 25 cases of potential clinically significant interactions with anticoagulant/antiplatelet agents identified [37] |
Ginkgo (Ginkgo biloba) | Surveillance studies (> 10,000 people), found 1.69% incidence of symptoms such as headache and gastrointestinal complaints [54]. Bleeding indicated in a few case reports [55]. May cause allergic hypersensitivity, including Stevens-Johnson syndrome [56‐58]. In cross-sectional survey of 1818 patients, 20 cases of potential clinically significant interactions with anticoagulant/antiplatelet agents identified [37]. Infrequent mild gastrointestinal discomfort has been reported when Ginkgo is taken with selective serotonin reuptake inhibitors (SSRIs) [59]. May interact with thiazides [60, 61], and nifedipine [62, 63] |
Ginseng (American, Asian, Chinese, Korean red; Panax ginseng, Panax spp. including P. ginseng and P. quinquefolius) | Long-term use of Panax and American ginseng associated with skin rash, itching, diarrhea, sore throat, loss of appetite, excitability, anxiety, depression, or insomnia [53, 64]. Few reports of headache, fever, dizziness/vertigo, blood pressure changes, chest pain, difficult menstruation, heart palpitations, leg swelling, nausea, vomiting, manic episodes in bipolar disorder, or Stevens-Johnson syndrome (may have been due to product contaminants) [53]. High intake of American ginseng may result in hypoglycemia in people with/without diabetes [65]. May interact with anticoagulants/antiplatelets [66, 67], diabetes medications [37], digoxin [68], estrogenic agents [69‐71], furosemide [72], monoaminergic agents [73‐75], nifedipine [76] |
Ginseng (American, Asian, Chinese, Korean red; Panax ginseng, Panax spp. including P. ginseng and P. quinquefolius) | Long-term use of Panax and American ginseng associated with skin rash, itching, diarrhea, sore throat, loss of appetite, excitability, anxiety, depression, or insomnia [53, 64]. Few reports of headache, fever, dizziness/vertigo, blood pressure changes, chest pain, difficult menstruation, heart palpitations, leg swelling, nausea, vomiting, manic episodes in bipolar disorder, or Stevens-Johnson syndrome (may have been due to product contaminants) [53]. High intake of American ginseng may result in hypoglycemia in people with/without diabetes [65]. May interact with anticoagulants/antiplatelets [66, 67], diabetes medications [37], digoxin [68], estrogenic agents [69‐71], furosemide [72], monoaminergic agents [73‐75], nifedipine [76] |
Melatonin (N-acetyl-5-methoxytryptamine) | May worsen depression and irritability. Sedative medications (CNS depressants) and benzodiazepines interact with melatonin [77] |
Omega-3 Fatty Acids, Alpha-Linolenic Acid | |
Valerian (Valeriana officinalis) | Mild impairments in concentration, processing, fatigue (less pronounced than with benzodiazepines) [91‐95], dizziness, and headache [96, 97]. Drug “hangover” and “withdrawal” effect has been reported with high doses [96]. Delirium, ameliorated by benzodiazepines, indicated in one case report [98]. Some develop a “paradoxical reaction” leading to nervousness, and use for longer than 2 months may result in insomnia [53]. Rare reports of hepatotoxicity with some preparations that include valerian [99] but may have been due to other components. May interact with CNS depressants [91, 92, 100]. In cross-sectional survey (n = 1818), 15 cases of potential clinically significant interactions with sedatives identified [37]. One case of SSRI use and valerian (with alcohol) indicated mental status changes [101] |