The single most important factors in disease progression are sleep and diet. This has been proven in studies of influenza propagation. Those that properly attend to those aspects of their lifestyle are far less likely to become seriously ill.
So if you’re demanding that your body operate on 5-6 hours of sleep a night, STOP! Start allocating a full eight hours to sleep. If you have trouble with the adjustment, check my one-sheet.
As concerns diet, again make adjustments. Fruits and vegetables have a complex chemistry that isn’t replicated by any artificial supplement – and it’s been proven that the natural source is more effective in support of healing and immunity. Eat whole fruits and vegetables, and lots of them. Pressed juices aren’t the same. You need the dietary fiber to keep your gut biome balanced – and that biome is also essential in the production of chemicals necessary to immune operation.
On top of these two factors, supplements may help to supercharge your immune system. Talk to a specialist and soon – high-quality supplements are rare. Most of what you get from supermarket supplements passes right through your gut.