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MFS(R) VARIABLE INSURANCE TRUST
MFS(R) EMERGING GROWTH SERIES
SUPPLEMENT TO THE CURRENT PROSPECTUS
The Emerging Growth Series may invest up to 25% of its net assets in foreign
securities including Emerging Market Securities. The section of the prospectus
entitled "Principal Risks" is amended to add the following:
Foreign Markets Risk - Investing in foreign securities involves risks relating
to political, social and economic developments abroad, as well as risks
resulting from the differences between the regulations to which U.S. and foreign
issuers and markets are subject:
o These risks may include the seizure by the government of company
assets, excessive taxation, withholding taxes on dividends and
interest, limitations on the use or transfer of portfolio assets,
and political or social instability.
o Enforcing legal rights may be difficult, costly and slow in
foreign countries, and there may be special problems enforcing
claims against foreign governments.
o Foreign companies may not be subject to accounting standards or
governmental supervision comparable to U.S. companies, and there
may be less public information about their operations.
o Foreign markets may be less liquid and more volatile than U.S.
markets.
o Foreign securities often trade in currencies other than the U.S.
dollar, and the fund may directly hold foreign currencies and
purchase and sell foreign currencies through forward exchange
contracts. Changes in currency exchange rates will affect the
fund's net asset value, the value of dividends and interest
earned, and gains and losses realized on the sale of securities.
An increase in the strength of the U.S. dollar relative to these
other currencies may cause the value of the fund to decline.
Certain foreign currencies may be particularly volatile, and
foreign governments may intervene in the currency markets,
causing a decline in value or liquidity in the fund's foreign
currency holdings. By entering into forward foreign currency
exchange contracts, the fund may be required to forego the
benefits of advantageous changes in exchange rates and, in the
case of forward contracts entered into for the purpose of
increasing return, the fund may sustain losses which will reduce
its gross income. Forward foreign currency exchange contracts
involve the risk that the party with which the fund enters the
contract may fail to perform its obligations to the fund.
Emerging Markets Risk - Emerging markets are generally defined as countries in
the initial stages of their industrialization cycles with low per capita income.
Investments in emerging markets securities involve all of the risks of
investments in foreign securities, and also have additional risks:
o All of the risks of investing in foreign securities are
heightened by investing in emerging markets countries.
o The markets of emerging markets countries have been more volatile
than the markets of developed countries with more mature
economies. These markets often have provided significantly higher
or lower rates of return than developed markets, and
significantly greater risks, to investors.
The date of this Supplement is December 10, 1999.
