Can multivitamins slow cognitive decline?

The Study

Recent evidence suggests that multivitamin use may delay cognitive aging and decrease risk of age-related dementia. The COSMOS randomized controlled trial conducted by Harvard Medical School put this hypothesis to the test.

In this study, 5,203 subjects over the age of 60 took a daily multivitamin for 2 years and took a battery of memory tests. Compared to the placebo group, the subjects taking a multivitamin had a statistically significant improvement in global cognition and episodic memory. The researchers estimated that taking the multivitamin was equivalent to reducing cognitive aging by 2 years.

American Journal of Clinical Nutrition 2024; 119:692-701

Take Home Message

The evidence is beginning to mount that taking a multivitamin has a positive impact on cognitive aging. Considering that they are inexpensive and have no negative side effects, it is not a bad idea to consider taking a multivitamin if you are older than 60.

Does being physically active attenuate the negative impact of sugar consumption?

The Study

Sugar sweetened beverages are known to have an adverse impact on cardiovascular health. A group of researchers at Harvard University wondered if being physically active reduced these negative effects. 

In this investigation, 65,730 women from the Nurses’ Health Study and 39,418 men from the Health Professional Follow-up Study had their sugar consumption and physical activity levels followed for 30 years.

The results were interesting:

-When looking at all subjects, those that consumed 2 or more sugar sweetened beverages per day had a 21% higher risk of cardiovascular disease when compared to those that never drank them.

-There was no association between diet beverage consumption and risk of cardiovascular disease.

-Participants meeting physical activity guidelines (greater than 7.5 MET hours per week) had no reduced risk when compared to subjects that did not meet physical activity guidelines (less than 7.5 MET hours per week).

American Journal Of Clinical Nutrition 2024; 119:669-681

Take Home Message

Whether you are physically active or not, it is a good idea to strictly limit sugar sweetened beverages.

Carbohydrates And Body Weight

In the 80’s and 90’s, dietary fat was the major focus of most weight loss strategies. Starting in the early 2000’s, the research literature started to show that carbohydrates were also important in weight maintenance. Most current fad diets manipulate the amount or type of carbohydrate permitted in some way. 

Harvard University’s Department of Nutrition recently published an impressive study examining the weight loss impact of different type of carbohydrate foods over a 24 year follow-up.

The Study

In this investigation, 136,432 men and women from Harvard’s Nurses’ Health Study, Nurses’ Health Study 2 and Health Professional Follow-up study had their 4 year weight change and diet measured for 24 years (Reference 1). 

The results were very interesting: (As a reference, 100 grams is just less than ½ of a cup)

-An increase in glycemic index and glycemic load were positively associated with weight gain.

-A 100 gram per day increase in added sugar resulted in a 4 year weight gain of 2 lbs.

-A 100 gram per day increase in refined grains resulted in a 4 year weight gain of 1.8 lbs.

-A 100 gram per day increase in potatoes and other starchy vegetables resulted in a 4 year weight gain of 5.7 lbs.

-A 100 gram per day increase in whole grains resulted in a 4 year weight loss of .9 lbs.

-A 100 gram per day increase in fruit resulted in a 4 year weight loss of 3.5 lbs.

-A 100 gram per day increase in non-starchy vegetable resulted in a 4 year weight loss of 6.6 lbs.

Conclusions And Recommendations

If you are trying to control your weight, you need to pay close attention to the type of carbs on your plate. However, there is no need to completely eliminate them. Carbohydrate foods are our best sources of fiber, vitamins, minerals and cancer fighting phytochemicals.

Focus on fruits, vegetables, legumes (beans and lentils) and whole grains (brown rice, quinoa and oatmeal).

Limit sugar, potatoes and refined grains like white rice, bread and pasta.

References

1) Wan Y, et al. Association between changes in carbohydrate intake and long-term weight changes: Prospective cohort study. British Medical Journal 2023; 382:e073939.