What else do you recommend, besides food and oil commodities? I don't know much about investment, but I'm trying to learn quickly. :o
Precious metals, and commodities in general, can be very volatile. If you see them as an investment (as I do), then you must look at the fact that they are not just driven by inflation in currency. In fact, this is a pretty small portion of their valuation. Gold's demand is particularly driven by the amount taken from mines and the amount of jewelry consumption. India/China with jewelry have a significant impact on the prices.
It's important to realize that PM's are not a 1-to-1 relation with inflation of the money supply. The money supply increased in the 80s and 90s, but gold and silver still got hammered. Usually when you have high inflation precious metals will go up, but they go up along with other commodities.
So with that being explained, you never want to put all of your eggs in one basket. Unless you are saving for a big purchase, I wouldn't even put more than 20% in cash. You need a certain amount of cash, stocks, commodities, bonds, etc. for your timeframe. If you are young, nothing beats inflation better than stocks.
Right now there are TONS of stocks that will do well from our inflationary environment. And usually they will do much better than precious metals. Oil drillers benefit the most from rising oil prices. Agriculture companies are benefitting from the rise of ethanol and more expensive food prices worldwide.
Look to invest in gold miners, oil drillers, and agriculture to bring in some cash as a result of rising commodity prices. It is a lot less risky than investing in the commodities directly.
Also, I've been doing very well investing in companies that are based in the United States, but more than 50% of their profits come from overseas. They sell the goods in stronger currencies, then convert it to dollars and it adds all the inflation back to their bottom line.