Japanese researchers found that DHA worked in a dose-dependent way to cut pain, and may act on opiate receptors
By Craig Weatherby

Last week, we reported that a Harvard study in mice found pain-reducing effects from compounds that rodents and humans alike produce from omega-3s.

For the details, see “Pain May be Relieved by Omega-3 Byproducts”.

The authors of that Harvard Medical School study suggested that omega-3-derived compounds called resolvins could present a safer new class of potent analgesic drugs.

Hard on the heels of those findings comes news of a supportive Japanese study, also performed in mice (Nakamoto K et al. 2010).

Unlike the earlier study, the Japanese researchers only gave mice DHA, which is one of the two key omega-3 fatty acids in human bodies and in fish.

Also unlike the Harvard study, they tested the effects of DHA on externally produced pain (heat and irritants) instead of pain induced by an injected inflammatory chemical.

DHA cuts pain to dose-dependent extents, and may act on opiate receptors
Omega-3 DHA is essential to the central nervous system's cells and systems, including the ones involved in pain sensing and transmission.

To evaluate the analgesic effect of DHA on pain, pharmacy researchers from Kobe Gakuin University fed the mice various doses of DHA 30 minutes before exposing them to painful stimuli (Nakamoto K et al. 2010).

The Japanese team reported that DHA reduced the rodents' pain symptoms in a dose-dependent fashion… in other words, the more DHA the mice got beforehand, the less pain they exhibited in response to (hopefully non-injurious) heat or irritants.

And DHA performed much better than the olive oil given to some “control” mice.

However, it is highly likely that the animals were given refined olive oil… not expensive extra virgin grade olive oil, which is known to possess analgesic powers related to the potent tyrosol-class antioxidants stripped from regular, refined olive oil.

Interestingly, the analgesic effects of DHA disappeared when mice were pre-treated with naloxone, an opiate-class analgesic that activates opioid receptors on human and mouse cells alike.

Humans and mice both produce opioid-type chemicals and their cells respond to opioid-type drugs such as opium, oxycontin, vicodin, and heroin. Opiate drugs ease pain and, in excess or in the absence of pain, can induce a drowsy euphoria and chemical addiction.

These findings suggest that DHA could, at least in part, cut pain by triggering opioid receptors on cells… without producing the “high” or addiction associated with true opiates.

This key detail can be explored further to help researchers devise safe, effective omega-3-derived pain relievers.

And together with the Harvard findings, the Japanese results support the idea that natural omega-3 oils may exert analgesic influences.

  • Nakamoto K, Nishinaka T, Mankura M, Fujita-Hamabe W, Tokuyama S. Antinociceptive Effects of Docosahexaenoic Acid against Various Pain Stimuli in Mice. Biol Pharm Bull. 2010;33(6):1070-2.