<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>109 - Disclosure - FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>4</Level><ElementName>us-gaap_FairValueDisclosuresTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="cx_01_January_2013_TO_30_June_2013" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;p align="justify" style="font-family: times new roman,times,serif; font-size: 10pt;"&gt;
      &lt;b&gt;NOTE 3 FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS&lt;/b&gt;
    &lt;/p&gt;
    &lt;p align="justify" style="font-family: times new roman,times,serif; font-size: 10pt;"&gt;The Company values its financial instruments as required by FASB ASC 320-12-65 (formerly SFAS No. 107, &amp;#8220;Disclosures about Fair Value of Financial Instruments&amp;#8221;). The estimated fair value amounts have been determined by the Company, using available market information or other appropriate valuation methodologies. However, considerable judgment is required in interpreting market data to develop estimates of fair value. Consequently, the estimates are not necessarily indicative of the amounts that could be realized or would be paid in a current market exchange.&lt;/p&gt;
    &lt;p align="justify" style="font-family: times new roman,times,serif; font-size: 10pt;"&gt;ASC Topic 820, Fair Value Measurement and Disclosures, defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. This topic also establishes a fair value hierarchy which requires classification based on observable and unobservable inputs when measuring fair value. The fair value hierarchy distinguishes between assumptions based on market data (observable inputs) and an entity&amp;#8217;s own assumptions (unobservable inputs). The hierarchy consists of three levels:&lt;/p&gt;
    &lt;table border="0" cellpadding="0" cellspacing="0" style="border-color: black; border-collapse: collapse; font-size: 10pt; font-family: times new roman,times,serif;" width="100%"&gt;
        &lt;tr valign="top"&gt;
          &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
          &lt;td align="left"&gt;Level one &amp;#8212;&lt;/td&gt;
          &lt;td align="left" width="85%"&gt;Quoted market prices in active markets for identical assets or liabilities;&lt;/td&gt;
        &lt;/tr&gt;
        &lt;tr valign="top"&gt;
          &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
          &lt;td align="left"&gt;Level two &amp;#8212;&lt;/td&gt;
          &lt;td align="left" width="85%"&gt;Inputs other than level one inputs that are either directly or indirectly observable; and&lt;/td&gt;
        &lt;/tr&gt;
        &lt;tr valign="top"&gt;
          &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
          &lt;td align="left"&gt;Level three &amp;#8212;&lt;/td&gt;
          &lt;td align="left" width="85%"&gt;Unobservable inputs developed using estimates and assumptions, which are developed by the reporting entity and reflect those assumptions that a market participant would use.&lt;/td&gt;
        &lt;/tr&gt;
    &lt;/table&gt;
    &lt;p align="justify" style="font-family: times new roman,times,serif; font-size: 10pt;"&gt;Determining which category an asset or liability falls within the hierarchy requires significant judgment. The Company evaluates its hierarchy disclosures each quarter.&lt;/p&gt;
    &lt;p align="justify" style="font-family: times new roman,times,serif; font-size: 10pt;"&gt;Assets and liabilities measured at fair value on a recurring basis are summarized as follows:&lt;/p&gt;
              &lt;table border="0" cellpadding="0" cellspacing="0" style="border-color: black; border-collapse: collapse; font-size: 10pt; font-family: times new roman,times,serif;" width="100%"&gt;
            &lt;tr valign="top"&gt;
              &lt;td align="left"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="center" colspan="7" nowrap="nowrap" width="36%"&gt;
                &lt;b&gt;Fair value measurement using inputs&lt;/b&gt;
              &lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" width="10%"&gt;
                &lt;b&gt;Carrying amount at&lt;/b&gt;
              &lt;/td&gt;
              &lt;td align="left" width="2%"&gt;&amp;#160;&lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr valign="top"&gt;
              &lt;td align="left"&gt;
                &lt;b&gt;Financial instruments&lt;/b&gt;
              &lt;/td&gt;
              &lt;td align="left" style="BORDER-BOTTOM: #000000 1px solid" width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" style="BORDER-BOTTOM: #000000 1px solid" width="10%"&gt;
                &lt;b&gt;Level 1&lt;/b&gt;
              &lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" style="BORDER-BOTTOM: #000000 1px solid" width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" style="BORDER-BOTTOM: #000000 1px solid" width="10%"&gt;
                &lt;b&gt;Level 2&lt;/b&gt;
              &lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" style="BORDER-BOTTOM: #000000 1px solid" width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" style="BORDER-BOTTOM: #000000 1px solid" width="10%"&gt;
                &lt;b&gt;Level 3&lt;/b&gt;
              &lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" style="BORDER-BOTTOM: #000000 1px solid" width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="center" nowrap="nowrap" style="BORDER-BOTTOM: #000000 1px solid" width="10%"&gt;
                &lt;b&gt;December 31, 2012&lt;/b&gt;
              &lt;/td&gt;
              &lt;td align="left" style="BORDER-BOTTOM: #000000 1px solid" width="2%"&gt;&amp;#160;&lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr&gt;
              &lt;td&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="10%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="10%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="10%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="10%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td width="2%"&gt;&amp;#160;&lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr valign="top"&gt;
              &lt;td align="left" bgcolor="#e6efff"&gt;Liabilities:&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="10%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="10%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="10%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="1%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="10%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="2%"&gt;&amp;#160;&lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr valign="top"&gt;
              &lt;td align="left"&gt;&amp;#160;&amp;#160; Derivative instruments &amp;#8211; Warrants&lt;/td&gt;
              &lt;td align="left" width="1%"&gt;$&lt;/td&gt;
              &lt;td align="right" width="10%"&gt;
                &amp;#160;
                &amp;#8212;
              &lt;/td&gt;
              &lt;td align="left" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" width="1%"&gt;$&lt;/td&gt;
              &lt;td align="right" width="10%"&gt;
                &amp;#160;173
              &lt;/td&gt;
              &lt;td align="left" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" width="1%"&gt;$&lt;/td&gt;
              &lt;td align="right" width="10%"&gt;
                &amp;#160;
                &amp;#8212;
              &lt;/td&gt;
              &lt;td align="left" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" width="1%"&gt;$&lt;/td&gt;
              &lt;td align="right" width="10%"&gt;
                &amp;#160;173
              &lt;/td&gt;
              &lt;td align="left" width="2%"&gt;&amp;#160;&lt;/td&gt;
            &lt;/tr&gt;
            &lt;tr valign="top"&gt;
              &lt;td align="left" bgcolor="#e6efff"&gt;Total&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="1%"&gt;$&lt;/td&gt;
              &lt;td align="right" bgcolor="#e6efff" width="10%"&gt;
                &amp;#160;
                &amp;#8212;
              &lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="1%"&gt;$&lt;/td&gt;
              &lt;td align="right" bgcolor="#e6efff" width="10%"&gt;
                &amp;#160;173
              &lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="1%"&gt;$&lt;/td&gt;
              &lt;td align="right" bgcolor="#e6efff" width="10%"&gt;
                &amp;#160;
                &amp;#8212;
              &lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="2%"&gt;&amp;#160;&lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="1%"&gt;$&lt;/td&gt;
              &lt;td align="right" bgcolor="#e6efff" width="10%"&gt;
                &amp;#160;173
              &lt;/td&gt;
              &lt;td align="left" bgcolor="#e6efff" width="2%"&gt;&amp;#160;&lt;/td&gt;
            &lt;/tr&gt;
        &lt;/table&gt;
    &lt;p align="justify" style="font-family: times new roman,times,serif; font-size: 10pt;"&gt;
      The carrying values of cash and cash equivalents, trade and other receivables and payables approximate their fair values due to the short maturities of these instruments. The carrying value of derivative instruments - Warrants, being classified as Level 2 financial instruments, was
      nil
      as of June 30, 2013.
    &lt;/p&gt;
    &lt;p align="justify" style="font-family: times new roman,times,serif; font-size: 10pt;"&gt;There was no asset or liability measured at fair value on a non-recurring basis as of June 30, 2013 and December 31, 2012.&lt;/p&gt;
    &lt;p align="justify" style="font-family: times new roman,times,serif; font-size: 10pt;"&gt;For stock-based derivative financial instruments, the Company uses Monte-Carlo simulation methods to value the derivative instruments at inception and on subsequent valuation dates. These stock-based derivative financial statements, including Series A Series B Warrants and Series C Warrants expired on December 16, 2012 and June 28, 2013, respectively (note 10).&lt;/p&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

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