The revised estimate by the head of the Edinburgh-based National CJD Surveillance Unit, Professor Robert Will, is based on the observation that most people to have died from new variant Creutzfeld Jakob disease (vCJD) have been relatively young.
The research, published in the journal Science, assumes that older people are likely to be more resistant to the disease.
Until recently, estimates of the number of deaths from eating infected beef have ranged from a few hundred to more than 130,000.
Latest figures from the Department of Health show there have been 111 confirmed or "probable" cases of vCJD since the infection was first recognised in 1996.
Contaminated meat
The illness can affect patients' speech and short-term memory and leave them requiring round-the-clock nursing care.
The relatively high incidence of the disease among young people has long been debated by doctors.
Last year, Dr Will said meat processing methods in the 1980s might have led to contaminated beef ending up on children's plates - a key factor in the new research by French and British scientists.
The average age of those who have died is 28, and only a handful of victims have been older than 53.
In contrast, 93% of people with "classic" CJD, which occurs sporadically for no known reason and is unconnected with contaminated meat, are over 50.
Genetic key
The scientists wrote: "Our prediction of the epidemic of vCJD lies in the 'optimistic' end of the ranges of previously published figures, and this low value is in favour of a large species barrier between cattle and humans."
Between 460,000 and 482,000 BSE-infected animals were slaughtered for human consumption before the ban on high-risk offal such as brain and spinal cord was introduced in 1989.
The number of people exposed to potentially infective doses through food may have been "extremely high", said the scientists.
However, only genetically susceptible people - about 40% of the population - were thought to be capable of getting the disease.