Saturated Fat And Attention

The Study

Can what you eat for lunch impact how your brain works in the afternoon? This interesting study attempted to find out. Fifty-one women had their cognitive performance measured by means of the Continuous Performance Test (CPT) both before and after 2 test meals, one high in saturated fat and one high in unsaturated fat.  The CPT measures attention, concentration and reaction time. After the high saturated fat meal, women had a statistically significant increase in distraction. American Journal of Clinical Nutrition 2020; 111:1150-58.  

Take Home Message

This is a fascinating study. I have seen evidence that high glycemic load carbohydrates can impact cognition, but this is the first study that I have seen that shows saturated fat can have a negative effect on brain function. As far as potential mechanisms, the researchers believe that saturated fat can cross the blood brain barrier and increase inflammation. This inflammation may interfere with cognitive function. 

Saturated fats such as butter, full fat dairy and fatty cuts of red meat have been shown to increase risk of heart disease and stroke. They may also influence your ability to concentrate. Focus on healthy vegetable sources of fats such as olive oil, canola oil, nuts, nut butters and avocados.

Red Meat And Colon Cancer

The Study

Colon cancer is the third most common cancer in the US and the second biggest cause of cancer related death. Sessile serrated lesions (SSL’s) are a type of colon polyp that are an alternative path to colon cancer. These newly identified lesions may account for up to 30% of all colon cancer diagnoses. In this interesting case-control study, the diet of subjects diagnosed with SSL’s were compared to healthy controls. Here are some of the most important results:

-When compared to subjects consuming the lowest amount of red meat, subjects consuming the most red meat had over twice the risk of developing SSL’s.

-When compared to subjects consuming the lowest amount of processed meat, subjects consuming the most processed meat had over twice the risk of developing SSL’s.

-When compared to subjects consuming the lowest amount of well-done red meat, subjects consuming the most well-done red meat had over twice the risk of developing SSL’s. American Journal of Clinical Nutrition 2020 111:1244-51.

Take Home Message

The results of this study offer further proof of the dangers of eating too much red and processed meats. 

Limit red meats like steak, pork and hamburger to 1 serving per week.

Strictly limit processed meats like bacon, salami and pepperoni.

When you do have red meat, don’t overcook it.

High Protein/Low Glycemic Diets And Weight Maintenance

The glycemic index and the percentage of dietary protein have previously been shown to be important factors when it comes to losing weight and keeping it off. An interesting older study that I recently came across examined the influence of protein and glycemic index on weight maintenance.

The Article

In this investigation, 773 subjects lost 8% of their initial body weight by following a low-calorie diet (Reference 1). Subjects were then randomized to one of five diets for 6 months:

High protein, Low Glycemic Index

High protein, High Glycemic Index

Low Protein, Low Glycemic Index

Low Protein, High Glycemic Index

A Control Diet.

Here are some of the most important results:

-The dieters that included a high protein component regained significantly less weight (over 2 lbs.) when compared to the diets with a low protein component.

-The dieters that included a low glycemic component regained significantly less weight (also over 2 lbs.) when compared to diets with a high glycemic index.

-Only the low protein/high glycemic group was associated with significant weight regain. They gained back 3.7 pounds.

-There was more dropout in the low protein and high glycemic index groups than in the high protein and low glycemic index groups.

Conclusions And Recommendations

Adding in a little protein and keeping your carbohydrates low glycemic can be a real boost to your weight loss efforts. Shoot for your protein to be 20-25% of calories. This is a practical and healthy level for you to shoot for. 

As far as glycemic index, focus on carbs like fruits, vegetables, legumes and whole grains instead of bread, pasta, white rice and sugar. 

These eating styles also resulted in less drop out in this particular study so they will make your diet easier to stay on.

References

1) Larsen TM, et al. Diets with high or low protein content and glycemic index for weight loss maintenance. New England Journal of Medicine 2010 363 2102-13.