Instead, they could stick with 100 frequently occurring words which were first listed in the Ladybird books of the 1960s.
In a fresh salvo in the row over phonics teaching following last week's Rose report for the Government, the research also questions one of the central claims of many advocates of the teaching of synthetic phonics.
Under the strategy, children are recommended to be taught to recognise 150 words at key stage 1, and a further 100 at key stage 2. But the research, by Jonathan Solity and Janet Vousden at Warwick university's Institute of Education, analysed a range of adult and children's books and two popular reading schemes and found that much of this learning could be counter-productive.
Only 16 regularly used words account for a quarter of written English, it found. And children taught the 100 frequently occurring words would be able to understand at least 48 per cent of all of the types of text studied.
By contrast, if they were taught the 50 next most-frequently occurring words, they would only gain understanding of an extra 2 per cent of the text in the reading schemes, and an extra 4 per cent in the adult books analysed.
The study, yet to be published, said tha this might explain why a seven-year-old who learnt the 100 frequently occurring words then took another six months to master the next 50, appeared to be making little progress with their reading.
Most controversially, the research said that, as they were mastering the 100 basic words and doing a set of tightly focused phonics work, the youngsters should move straight on to real books, rather than the controlled reading schemes that are popular in many schools.
Children were just as likely to find words they recognised in adult or children's books as in the reading schemes, it found. But they were more likely to find the real books interesting and useful in encountering new words in a variety of contexts.
This last claim pits Dr Solity against many advocates of synthetic phonics, who were backed by last week's interim Rose report, and some of whom recommend the use of reading schemes where children are exposed only to vocabulary they already know.
The study, funded by the Leverhulme Trust, supports an approach to reading which Dr Solity has been pioneering in more than 200 schools over the past 10 years.
The Early Reading Research scheme has seen children taught the 100 words and 61 links between letters and their sounds.
Dr Solity said pupils taking part were on average six months ahead of their expected reading age by the time they reached seven. Only 2 per cent of youngsters had serious reading difficulties, he said.
Mr Rose said he would be looking at Dr Solity's research in detail, and visit some of the ERR schools before publishing his final report. Dr Solity's work had much in common with other phonics programmes in its structured, incremental approach to teaching word recognition, he said.
Mr Rose said: "This is all very plausible stuff."
Sue Palmer, a literacy consultant, said that lists of regularly used words had been around for a long time. The key element was to teach phonics to youngsters fast and first, before introducing them to books.
Andrea Quincy of Harcourt primary, which publishes popular reading schemes, said: "Educational publishers have sought over the last few years to make the reading schemes we produce much richer than they used to be, so they are now much more akin to real books."
The Department for Education and Skills said it did not comment on unpublished research.
100 words that set children on the path to literacy
* a, about, after, all, am, an,and, are, as, at, away,
* back, be, because, big, but, by
* call, came, can, come, could
* did, do, down
* for, from
* get, go, got
* had, has, have, he, her, here, him, his
* I, in, into, is, it last, like, little, live, look
* made, make, me, my
* new, next, not, now
* of, off, old, on, once, one, other, our, out, over
* saw, said, see, she, so, some
* take, that, the, their, them, then, there, they, this, three, time, to, today, too, two
* up, us
* was, we, were, went, what, when, will, with