"Because yield returns are so low QE has forced Capital into non-yielding assets which has produced a commodities boom. For example, Between 2010 and 2011 the S.P GSCI Agricultural Index of crop prices doubled and that equates directly to higher food prices."
Conclusion.
The increased participation by financial investors in commodity futures markets over the last
decade has been quite substantial. In principle this could have influenced the risk premium,
and Hamilton and Wu (forthcoming) found significant changes in the behavior of the risk
premium on oil futures contracts before and after 2005. In this paper we studied data
since 2006 to look for a systematic relation between the notional value of commodity futures
contracts held on behalf of index-fund investors and expected returns on futures contracts.
We found essentially no relation for the 12 agricultural commodities for which the CFTC reports such positions. We reviewed evidence that positions in crude oil contracts imputed
from the reported agricultural holdings could help predict crude oil futures returns, and noted
that the methodology for such imputation could be generalized to make use of all the available
data. We confirmed that these imputed holdings appear to help predict crude oil returns over
2006-2009, though this is closely related to the dynamics of index investing during the Great
Recession, and indeed the same imputed holdings also appear to predict stock returns over
that period. We found, however, that both relations broke down when trying to describe the
data since 2009.
Our overall conclusion is thus consistent with most of the previous literature,
there seems
to be little evidence that index-fund investing is exerting a measurable effect on commodity futures prices. As noted in the introduction, even if one could demonstrate that index-fund buying on commodity future prices, it it would be a separate challenge to explain hows this could also end up changing the equilibrium spot price.
We conclude that it is difficult to find much empirical foundation for a view that continues to have a significant impact on
policy decisions.
http://dss.ucsd.edu/~jhamilto/commodity_index.pdf