Diet and Cognitive Function

Question 1

What is the mediterranean diet?

Answer 1

rich in fruit & vegetables (FVs), plant derived products & seafood, relatively low alcohol intake, low intake of meat, saturated fatty acids & added sugar

Question 2

What were the primary outcomes of the PrediMed study?

Answer 2

• both Mediterranean diet groups showed significant reduction in the rate of CVD indicators (stroke, myocardial infarction, death)
• 30% relative risk reduction

Question 3

What were the 3 conditions in the Predimed study?

Answer 3

1. Mediterranean diet supplemented with extra-virgin olive oil (something like 2ltrs/week)
2. Mediterranean diet supplemented with nuts.
3. Control diet encouraging low-fat food items

Question 4

What were the 3 composite cognitive measures in the PrediMed study?

Answer 4

1. Memory
2. Frontal
3. Global

Question 5

What were the cognitive outcomes of the PrediMed study?

Answer 5

• Global = both med groups sig different from control (didnt decline as much)
• Frontal = control declines, no change in med, oil slight improvement
• Memory = control declined, med stayed similar, slight improvement with nuts

Question 6

What are some criticisms of the predimed study?

Answer 6

• protocol changed during the trial
• losses to follow up in the low-fat group – possible bias?
• true low-fat diet was not achieved by the control group
• Participants lived in a Mediterranean country –generalisable?
• implausible P value patterns when comparing the baseline characteristics of the three arms.
• enrolment of household members without randomisation;
• assignment of participants to study arms based on clinic site rather than true randomisation
• lack of blinding

Question 7

In the Lothian birth cohort study, what was adherence to Mediterranean style diet related to?

Answer 7

better global- and domain-specific cognitive functioning, independently of other lifestyle factors, health variables, and childhood IQ but not MRI measures of brain structural integrity

Question 8

What is the role of hippocampal neuron cells?

Answer 8

• Increase spatial memory capacity,
• Reduce interference between memories (pattern separation)
• Add information about time to new memories (‘I did that when..’)
• Are involved in forgetting of established context-¬memories

Question 9

What is pattern separation?

Answer 9

Reduces interference between memories i.e. helps us to distinguish similar memories

Question 10

Where is info about similar items coded in the brain?

Answer 10

Dentate gyrus

Question 11

Reaction times for pattern separation are related to?

Answer 11

Cerebral blood flow/volume

Question 12

How do cocoa flavanols improve pattern separation

Answer 12

Cocoa falvanols increased blood volume and improved task performance

Question 13

What is the klotho gene?

Answer 13

• An age supressor gene

- extends lifespan of mice by 20-30%

Question 14

What the Klotho up-regulated by?

Answer 14

• Klotho is upregulated by IF (intermittent fasting) and its increased expression in the hippocampus is associated with increased hippocampal neurogenesis and improved retention memory.

Question 15

Which diet is best for pattern separation?

Answer 15

Intermittent fasting and caloric restriction

- distinction between the 2 is not clean

Question 16

Using the Lothian birth cohort, what did Corley find about adherence to the Mediterranean style diet?

Answer 16

• better verbal ability, global function, visuo-spatial ability and memory
• However, these associations were reduced by 50% when adjusting for childhood cog ability
• after adjusting only verbal ability remained
• no dietary pattern was associated with brain volumes of white matter

Question 17

Associations in the lothian cohort were likely driven by what component of a Mediterranean diet?

Answer 17

• green leafy veg

- low red meat consumption