New study from Elizabeth Platz (Johns Hopkins) [1].
Most here will be aware of choline from PCa imaging (18F-choline-PET/CT, 11C-choline PET/CT ...) or eggs (one yolk has about 115 mg of choline, depends on the size). If PCa cells have a hunger for enough choline to make it a viable PET scan tracer, then one must presumably stay away from eggs. If you have seen the Greger vegan video on eggs, you may have already stopped eating them, but some perspective is required.
Choline is an essential nutrient - it has to be in the diet. An adequate daily intake is ~550 mg. While deficiency is rare, it's not easy take in an excessive amount each day.
550 mg from a single rich source:
- 5 eggs
- 6 oz beef liver
- 3 lb cauliflower
- 30 oz chicken
- 23 oz cod
- 7.4 cups almonds
While eggs are often touted as the richest source of choline, one egg will supply only 20% of an adequate supply. I had one for breakfast. Making up the other 80% from the above list would be a challenge for me - & most foods have far less choline.
If one were to intentionally restrict choline intake, the result would be fatty liver disease & muscle damage.
What's the link between choline & betaine? They are both methyl donors. It may be a good idea to limit methy intake since PCa cells want to be hypermethylated. The cancer will invariably methylate - silence - the DNA promoter regions for tumor suppressor genes, if the methyl supply is good.)
The body can produce the non-essential amino acid betaine from choline, although most of us have plenty in the diet.
From the new study:
"We included 6,528 men (24.4% African American) without a cancer diagnosis at baseline (1987-1989) followed through 2012. Dietary intake was assessed using a food frequency questionnaire coupled with a nutrient database."
"Choline intake was not associated with total or lethal PCa or with PCa death in men with PCa. Betaine intake was inversely associated with lethal, but not total PCa risk or with PCa death in men with PCa. Our results do not support the hypothesis that higher choline intake increases lethal PCa risk, but do suggest that higher betaine intake may be associated with lower lethal PCa risk."
I wish this would be the end of the choline-egg debate, but I doubt it.
The protection offered by betaine is a surprise. I never have the beet salad in my favorite restaurant because of the methyl in the betaine. Appears that there is something other than the methyl that needs investigating.
{The Atherosclerosis Risk in Communities (ARIC) study published a paper last year [2]:
"Aspirin use was not associated with prostate cancer incidence. However, aspirin use was inversely associated with prostate cancer mortality [HR, 0.59 ..."
& more recently [3]:
"Our findings indicate hyperglycemia is associated with an increased risk of lethal and fatal prostate cancer, but not total prostate cancer incidence."
hyperglycemia = elevated insulin; insulin resistance}
-Patrick
[1] ncbi.nlm.nih.gov/pubmed/308...
Choline and APC. 
