When Japanese researchers said earlier this year that eating whale meat could help prevent dementia and memory loss, the news provoked snorts of derision -- it couldn't be real science, went the retort.

Despite protestations of academic rigour from the men and women who do the work, anything involving the words "Japan", "whaling" and "research" suffers from a credibility gap in the court of global public opinion.

Tokyo was told last year by the United Nations' top legal body that the programme of "lethal research whaling" it has carried out in the Southern Ocean for nearly two decades was a fig leaf for a commercial hunt.

Now Japan is going back to the scientific panel of the International Whaling Commission (IWC) at a meeting in San Diego that began Tuesday, to try to convince them there is a genuine need for the research that they say is being carried out when they slaughter marine mammals whose meat ends up on the dinner table.

Japan's research whaling programme "doesn't appear to fulfil basic criteria that all scientists naturally strive towards", said Atsushi Ishii, associate professor of environmental politics at Tohoku University in northeastern Japan.

"For example, there was no reasonable explanation as to how catch ceilings were worked out and... there have been few peer-reviewed articles.

"Scientific research on this scale usually involves cooperation with other projects" for efficiency and to avoid duplication, but Japan has steadfastly gone it alone, he added.

- Loophole -

Japan has hunted whales for a few hundred years, but the industry really took off after World War II to help feed a hungry country.

While other leading industrial nations -- including the United States and Britain -- once hunted whales, the practice fell out of favour, and by the 1980s, commercial whaling was banned.

Norway and Iceland ignore the ban, but Japan uses a loophole that allows for so-called "lethal research".

"The purpose of Japan's research is science -- science that will ensure that when commercial whaling is resumed, it will be sustainable," the Institute of Cetacean Research (ICR), the body charged with overseeing the whaling programme, insists on its website.

The ICR says this means it needs to keep careful tabs on the whale population, by determining, amongst other things, the average life expectancy of the creatures, their exposure to pollutants and their diet.

The only accurate way to measure these criteria, they say, is to kill the animals to examine their stomach contents, the condition of their organs and the thickness of their blubber.

Responding to the UN court decision, Japan has now submitted a new research proposal to the IWC, setting a Southern Ocean catch target of 333 minke whales -- a two-thirds cut of the previous target -- and limiting the programme to 12 years, instead of being open-ended.

Anti-whaling campaigners insist most of what needs to be learned about whales can be gleaned by observing them, taking biopsies or examining faecal discharge.

Japanese whaling research "is not considered genuine science," Greenpeace Japan activist Junichi Sato told AFP.

Scientists who argue for it are "speaking in order to help realise the political intention of resuming commercial whaling, rather than on grounds of scientific, objective judgement".

- Suspicion -

Away from the thorny issue of stock counting, research on possible health benefits of consuming whale meat is tarred with the same brush.

In March this year tests on mice revealed consuming balenine -- a substance found in whale meat -- mitigated the effects of Alzheimer's Disease.

Greenpeace's Sato said there had to be automatic suspicion about research like this, which was carried out in association with the ICR and could be a foil to help stimulate flagging demand for whale meat.

Professor Seiji Shioda of Hoshi University in Tokyo, who did the work, refuted any suggestion it could be tainted by politics.

"I don't understand why the study should be labelled as unscientific," he told AFP.

"Based on scientific data, I believe there surely is a meaningful substance" in whales' bodies, he said, noting they live long lives and continue to carry out complex navigation in old age.

"Whales are wonderful creatures but not much is known about their functionary mechanism... We need to proceed with scientific analysis."

Tohoku University's Ishii says ironically, the moratorium on commercial hunting is one of the few things that has kept whaling alive in Japan.

By around the turn of this century, the industry was no longer commercially viable. Japan "could not have extended the life of whaling without the moratorium".

Given every Antarctic mission results in a loss, the fisheries agency actually wants to pull out, he said, but a group of pro-whaling lawmakers will not allow it.

"They think it would look like Japan's succumbing to (environmentalists') or Australian demands," he said.