* FTSE 100 snaps five-day winning streak
* Commods, banks under pressure after good run
* Gains in defensive issues limit losses
By Tricia Wright
LONDON, Sept 18 (Reuters) - Britain's top share index drifted lower early on Friday, as investors took profits after a five-day winning run, with commodity stocks and banks taking the most points off the index.
At 0816 GMT, the FTSE 100 was 6.01 points or 0.1 percent lower at 5,157.94, having closed up 0.8 percent at 5,163.95 on Thursday, its highest level since late September last year.
"It's been a fantastic week, we blazed a trail -- we're another 2.5 percent up. We've seen the FTSE go up 46 percent in six months -- you can't blame people for taking a pause for reflection," said David Buik, senior partner at BGC Partners.
The FTSE 100 has risen over 21 percent this quarter and is on track to post its best percentage quarterly gains since the index was launched in 1984.
But it is still down 4.9 percent from a year ago before the collapse of Lehman Brothers which sent a shockwave around the world.
"The bubble doesn't really show any signs of bursting because the alternative asset classes are very unattractive; i.e., do you really want to buy gold starting at $1,013? Probably not. Do you want to put money on deposit? Probably not," Buik said.
Miners were the biggest fallers, under pressure against a background of softer metals prices.
Antofagasta, Xstrata, Lonmin and BHP Billiton dropped 0.7 to 2.4 percent.
Energy stocks also fell as crude prices dipped below $72 a barrel on Friday, as a retreat by Asian equities markets weighed on sentiment and encouraged investors to take profits.
BG Group fell 1.4 percent, while BP dropped 0.3 percent and Cairn Energy shed 2 percent.
A broker downgrade weighed on Tullow Oil, off 1.6 percent, with Citigroup cutting its recommendation on the oil explorer to "hold" from "buy" after strong gains over the past week and oil find news on Thursday.
Banks were on the back foot. Lloyds Banking Group fell 1.2 percent after the part-nationalised lender said it was in talks over scaling back its participation in a state-backed scheme to insure it against credit losses, and was also weighing up alternatives to the scheme.
Heavyweight HSBC fell 0.3 percent and Standard Chartered shed 1.1 percent, while Royal Bank of Scotland and Barclays dropped 1.5 percent and 1.1 percent, respectively, despite target price hikes by Goldman Sachs.
British Land fell 1.2 percent. Britain's second largest real-estate firm is poised to conclude the long-awaited sale of half of its Broadgate office complex to private equity firm Blackstone, the Financial Times reported on Friday.
DEFENSIVES LIMIT LOSSES
Gains in defensive beverages and tobacco and pharmaceutical stocks helped limit the FTSE 100's losses, as investors' appetite for risk ebbed and flowed.
Diageo rose 1.1 percent, Imperial Tobacco added 0.2 percent and GlaxoSmithKline added 1.4 percent.
The pharmaceutical firm is in talks to buy a 5 percent stake in Indian drug maker Dr Reddy's Laboratories in a deal likely to be valued at $150 million, the Economic Times reported on Friday, citing sources privy to the development.
Kingfisher climbed 2.2 percent, topping the blue-chip leaderboard, after the home improvements retailer's strong first-half results a day earlier prompted a round of price target hikes by brokers.
Standard Life was also lifted by positive broker comment, gaining 2 percent as Goldman Sachs raised its recommendation on the insurer to "buy" from "neutral".
Investors will keep an eye on UK public sector borrowing figures for August due at 0830 GMT.
Economists polled by Reuters expect net public sector borrowing to hit 17.5 billion pounds in August, after reaching 8.016 billion pounds in July. (Editing by Hans Peters)