TORONTO -- The health-care sector helped boost Canada's main stock index on Tuesday despite a slide in energy prices, as the loonie lost ground.

The S&P/TSX composite index was up 10.52 points to 16,114.03, with shares of Valeant Pharmaceuticals International Inc. (TSX:VRX) up $1.73, or 6.54 per cent, to $28.18 at the closing of markets.

Earlier on Tuesday, the commodity-heavy index had flirted with a new record, after setting an intraday high of 16,142.80.

South of the border, markets were mixed as investors awaited Wednesday's announcement by the U.S. Federal Reserve, which is expected to raise short-term interest rates by 0.25 of a percentage point. While inflation has remained low, the central bank has seen a path to gradually raise rates as the economy and labour market have strengthened.

On Wall Street, the Dow Jones industrial average advanced 118.77 points to 24,504.80 and the S&P 500 index added 4.12 points to 2,664.11 -- capping off three straight trading sessions in which these indices have surpassed record highs. The Nasdaq composite index was down 12.76 points to 6,862.32.

"The hike tomorrow by the Fed is baked into the cake," said Luc de la Durantaye, managing director of CIBC Management.

"What would be important is the tone of the Fed tomorrow. They may indicate through their updated forecast that they're more confident about their inflation outlook. They might even mention something about the tightness of the labour market. We may have a bit of a hawkish hike tomorrow which would be supportive of the U.S. dollar."

In currency markets, the Canadian dollar closed at an average trading price of 77.69 cents US, down 0.11 of a U.S. cent.

De la Durantaye attributed part of loonie's drop to falling oil prices, which had seen sharp increases over the past three trading sessions.

The January crude contract tumbled 85 cents to US$57.14 per barrel.

Elsewhere in commodities, the January natural gas contract gave back 15 cents to US$2.68 per mmBTU. The February gold contract fell US$5.20 to US$1,241.70 an ounce and the March copper contract was up a cent at US$3.02 a pound.