Maybe Diet Sodas Are Not the Answer, after All . . .

The American Stroke Association held its International Conference recently, resulting in some interesting findings regarding diet sodas and stroke risk. In two presentations, Dr Hannah Gardener presented results from the University of Miami analysis of the Northern Manhattan study. The first concerned a link between diet soda consumption and the risk of stroke, and the second concerned sodium intake and stroke risk.

The Northern Manhattan study included more than 2500 individuals over 40 living in New York City; their average age was 69, with 50% Hispanic, 25% black, and 20% white participants. A food frequency questionnaire was completed at baseline. It showed that 35% of them did not drink either regular or diet soda, and only 24% drank any amount of diet soda. The main finding in this regard was that over an average follow-up of more than 9 years there was an increased risk of having a vascular event (stroke, heart attack, or cardiac death) with daily diet soda consumption. There was no such relationship with consumption of regular soda or lesser amounts of diet soda. Drinking diet soda was also associated with being white, having diabetes, a low high-density lipoprotein cholesterol, increased waist circumference and body mass index, and peripheral vascular disease. The relationship between regular diet soda consumption and vascular events persisted after corrections for these cardiovascular risk factors.

Using the same data base from the Northern Manhattan study, Dr Gardener also found that excessive sodium intake was linked to an increased risk of stroke those participants with the highest daily sodium intake had a nearly threefold increased risk compared with those who met the recommended level of 1500 mg a day or less. The analysis showed that every 500 mg per day increase in sodium intake was associated with an 18% relative increase in the risk of stroke. Those participants who consumed the most – more than 4000 mg per day – had a 2.67-fold increase in the risk compared with those within the 1500 mg per day target.

Putting these two sets of results together, it seems that diet soda may carry intrinsic risk of provoking a vascular event – possibly because people with poor dietary habits who are trying to lower their calorie intake may continue to eat sweet foods but replace regular sodas by diet sodas, and thus keep their salt intake high. However, the study has attracted a lot of criticism.  One authority said: "They didn't look at how much salt they took in, they didn't look at what other foods they ate. Those things we know are associated with stroke and heart attack. They didn't even look at obesity over time. And so to conclude from this, that it's all from the diet soda, just makes no sense whatsoever."  Well, this may be so.  But I still think it's better to drink water instead of any sort of soda or sweetened fruit drink.