The relationship between financial news consumption and investment decision quality is negative. This is not because financial news is uniformly worthless but because the ratio of actionable signal to disruptive noise in financial media is sufficiently low that more consumption produces more noise exposure without proportional improvement in decision quality. The investor who reads two hours of financial news daily is not twice as well-informed as the one who reads one hour; she is exposed to twice the noise, twice the emotionally provocative content, and twice the volume of market commentary that will generate decisions she would not otherwise make.
The information value of financial news is highly concentrated in a small fraction of its total output. Genuinely significant developments—major regulatory changes that structurally affect industries, significant earnings revisions that change the fundamental valuation of a business, macroeconomic shifts that alter the expected return on broad asset classes—occur rarely and are quickly incorporated into prices. The vast majority of financial news output consists of commentary on daily price movements, short-term economic data points, analyst opinions that add little to consensus, and market predictions that the evidence consistently shows are unreliable. This high-noise, low-signal output is what fills the daily news cycle, because genuine investment-relevant information is too rare to fill a continuous news cycle.
The specific damage that high news consumption causes operates through the mechanism of action generation. Each piece of news that reaches the investor creates an implicit question: should I do something about this? In most cases, the correct answer is no—the news is noise, it is already priced, and the appropriate response is to continue holding. But the question itself has a cost, because answering it correctly requires the expenditure of cognitive resources that could be directed elsewhere, and because the probability of answering it incorrectly—of deciding that action is warranted when it is not—is non-trivially positive. High news consumption therefore generates a high volume of implicit action questions, each of which is an opportunity for an unnecessary and potentially damaging portfolio decision.
The empirical literature on trading frequency is relevant here. Studies consistently show that higher trading frequency is associated with worse returns, after controlling for other variables. This relationship is not causal in the direct sense that trading destroys returns; it is evidence that the decisions that drive higher trading frequency—the responses to news events, the reactions to short-term price movements, the implementation of market views—are, in aggregate, return-degrading. The news consumption that generates these decisions is not the cause of the poor returns; it is the input to the decision process that produces them.
The practical corrective is not an absence of financial news consumption but a radical reduction in its frequency and scope. The investor who reviews financial news weekly rather than daily, and who limits his news consumption to sources with longer analytical time horizons rather than daily commentary, will find that the actionable information he receives is roughly the same—because genuinely important developments persist across the week—while the noise exposure is dramatically reduced. The reduction in noise exposure reduces the volume of implicit action questions his portfolio is subjected to, reducing the opportunity for the poor decisions that news-reactive investing generates.