That's the message from a long-term study of adults with type 2 diabetes.
What's the payoff? Less likelihood of a heart attack and a healthier cardiovascular system, for starters, according to the findings published in The New England Journal of Medicine.
Curbing Blood Sugar
Some 5,100 British adults newly diagnosed with type 2 diabetes were assigned to one of those treatment plans. They stayed with the study for six to 20 years.
When the study ended, it was clear that complications in tiny blood vessels were rarer in the intensive drug therapy groups than in the diet-only group.
That advantage was still paying dividends a decade later.
When the study ended in 1997, the patients were free to follow whatever type 2 diabetes treatment they chose with their doctors. Most started taking diabetes drugs.
That doesn't mean they abandoned diet; it just means that they were all allowed to take drugs, too. A healthy diet is a staple of diabetes care.
Over the next 10 years, people formerly in the intensive drug therapy group were less likely to have a heart attack or develop diabetes-related complications, compared with people who had been in the diet-only group.
The early, intensive approach to blood sugar control amounted to a head start. The researchers -- who included Rury Holman, FRCP, of Churchill Hospital in Oxford, England -- call that a "legacy effect."
Blood Pressure: Keep It Down
Holman's team also compared intensive and not-so-intensive approaches to blood pressure among the diabetes patients in their study. High blood pressure, like diabetes, makes heart disease (and a host of other serious conditions) more likely.
More than 1,100 participants were either assigned to take an ACE inhibitor or a beta-blocker to reach a certain blood pressure goal. For comparison, other patients with high blood pressure got an easier blood pressure goal and didn't have to take ACE inhibitors or beta-blockers.
When the study ended, the patients who took the intensive approach were less likely to have died from diabetes, had a stroke, or developed diabetes-related complications.
But two years later, when the patients could handle their blood pressure however they wanted to, it was a different story.
By then, blood pressure had crept up in the patients who had been in the intensive group, and dropped in the comparison group. That erased the benefit gaps between the groups; there was no "legacy effect."
The bottom line: Optimal blood pressure control is "of major importance... in patients with type 2 diabetes but must be maintained if these benefits are to be sustained," Holman and colleagues conclude.