Zinc and Wound Healing

There is no question that severe zinc deficiency impairs wound healing, possibly
via multiple mechanisms.However, it is less clear if oral zinc supplements can help
wound healing by correcting marginal zinc deficiency, or if zinc can have benefits
beyond correcting deficiency. Much of the support for recommending zinc supplements
for wound healing have come from topical zinc applications, which may
not be relevant to oral supplementation. Some other support has been derived from
an old study on young men with wounds caused by excision of pilonidal sinuses.149
This study reports that zinc helps subjects who have low serum zinc. In addition,
there are some studies on zinc and certain types of ulcerations. A meta-analysis
concludes that while oral zinc sulfate does not appear to aid healing of leg ulcers,
it might be beneficial in those with venous leg ulcers and low serum zinc. These
two considerations have led to the attitude that zinc supplements help with wound
healing, but only in people with some degree of zinc deficiency. Unfortunately, this
conclusion has been built on relatively little data. For one thing, the venous ulcer
data may not be relevant to other types of wound healing. Moreover, the older
study149 has not had confirmation. Furthermore, even if zinc is effective for wound
healing when there is low serum zinc, this could reflect that effectiveness is tied not
to poor zinc status, but rather the presence of inflammation, which can also depress
serum zinc.3

In this opinion, we still know very little about any of the following:
• The degree of zinc deficiency necessary to impair wound healing
• Whether zinc supplements can help with wound healing in the absence
of any deficiency
• What range of wound types might be helped by zinc supplements

This sort of uncertainty is echoed in an opinion article that appeared awhile ago
in the journal Lancet. Although a number of years have passed since that article
appeared, not much new research has occurred in this area.
In this author’s opinion, since low-dose zinc supplementation probably won’t
hurt healing, such supplementation is reasonable in people recovering from wounds.
On the other hand, high-dose zinc supplements would not be a good idea because
of possible antagonism of the absorption of copper, which is also needed for wound
healing.