UPDATE 2-Profits for restaurant operator Alsea slide by a third, missing expectations

(Adds details on revenue in paragraph 4, currency and consumption in paragraphs 7-8)

MEXICO CITY, April 23 (Reuters) - Fast-food chain operator Alsea reported on Tuesday a 34% fall in its first-quarter net profit, driven mainly by foreign exchange swings and weaker consumption in some of its markets.

Net profit during the January-to-March period for the Mexico-based company stood at 404.1 million pesos ($24.3 million), according to a filing, coming in under expectations.

Alsea, which operates chain restaurants and cafes including Starbucks, Burger King and Domino's Pizza , also reported a 3% rise in quarterly revenue compared with the same period last year to total 18.2 billion pesos.

Quarterly revenue would have risen more than 12% had it not been for the impact of currency exchange fluctuations, the company said in a separate statement.

Analysts polled by LSEG had forecast a quarterly net profit of 484.9 million pesos from revenues seen at 18.3 billion pesos.

Alsea operates in a dozen countries across Europe and Latin America, and registers more than half its sales in Mexico and close to a third across western Europe.

The foreign exchange impact in Alsea's home market of Mexico was especially significant; Mexico's peso currency appreciated more than 8% against the U.S. dollar in the January-to-March period versus a year earlier.

In the statement, CEO Armando Torrado nodded to the peso's "challenging" strength, which made Mexican costs more expensive in dollar terms, as well as lackluster consumption, primarily in France and South America.

During the first three months of this year, the company's Mexico sales rose by 13%, while sales in South America fell by 18%.

Alsea deployed 940 million pesos in capital spending during the quarter.

Last month, Chief Financial Officer Federico Rodriguez said the company plans to invest 6 billion pesos this year. ($1 = 16.5310 Mexican pesos at end-March) (Reporting by Valentine Hilaire, Marion Giraldo and Aida Pelaez Fernandez; Editing by David Alire Garcia and Jonathan Oatis)