It appears that higher inflation is not fleeting.As investing in commodities are the best practices in an inflationary environment, theSPDR S&P Metals & Mining ETF XME and theSPDR S&P North American Natural Resources ETF NANR have gained about 5% each past month. SPDR S&P Metals & Mining ETF (XME): ETF Research Reports The Dow Jones and the S&P 500 lost 4.6% and 4.9%, respectively, while the Nasdaq Composite Index shed 9% in the first quarter (read: U.S. Stocks Log Worst Q1 in 2 Years: Top-Ranked ETFs Shine).