ABU DHABI, Aug 29 (Reuters) - NMC Health said on Monday it had expanded into Saudi Arabia through an investment and an acquisition, the first foray into the wider Gulf for the United Arab Emirates-based healthcare provider.

This enabled it to raise its guidance for 2017 group EBITDA (earnings before interest, tax, depreciation and amortisation) to $300 million from the previously-disclosed $290 million, NMC said in a statement.

NMC, along with other companies, is tapping into substantial growth in the sector as the Gulf's increasingly wealthy population becomes more susceptible to lifestyle diseases such as diabetes.

It has taken a majority stake in a new 120-bed hospital in Jeddah by putting $4 million of equity into the operating company.

NMC will also provide a $9 million two-year loan to its subsidiary Provita, which will manage the business.

It has also acquired a 70 percent stake in As Salama Hospital in the kingdom's Eastern Province for $28 million, adding 140 beds to its total count.

"This represents another major advance towards our objective of developing a regional leader in the field of specialist long-term care," said B.R. Shetty, chief executive of NMC.

As well as plans to revamp the existing facilities at Khobar-based As Salama, NMC said its strategy includes possible investment and expansion in the central region of Saudi, which includes the capital, Riyadh.

The London-listed firm now has 1,135 operational beds across its network, which is primarily in the UAE but also includes Spanish fertility firm Clinica Eugin.

It generated EBITDA of $115.9 million in the first half of 2016, up 68.2 percent over same period of last year.

(Reporting by Stanley Carvalho; Editing by Ruth Pitchford) ((stanley.carvalho@thomsonreuters.com; + 9712 6444431; Reuters Messaging: stanley.carvalho.thomsonreuters.com@reuters.net))