Not really. Excess sugar consumption has a direct negative impact on the consumer. The only commons here is health care.

The Commons here is the 'market for healthy food'.

The first entity that adds extra sugar to their food to gain mind share inevitably causes the rest of the competitors to all add more sugar, bringing them back to parity while also destroying 'the market for healthy food'.

This race towards everyone being worse off because of economic incentives not to be left behind is a tragedy of the commons in the market sense.

Sounds like a tragedy of the commons …

Not in America.