Little green balls of death!

[Todd Allen]

From Al's papers' citations:

 

Intake of glucosinolates and risk of coronary heart disease in three large prospective cohorts of US men and women.
Ma L, Liu G, Zong G, Sampson L, Hu FB, Willett WC, Rimm EB, Manson JE, Rexrode KM, Sun Q.
Clin Epidemiol. 2018 Jun 29;10:749-762. doi: 10.2147/CLEP.S164497. eCollection 2018.
PMID: 29988715
https://www.ncbi.nlm...clep-10-749.pdf
https://www.ncbi.nlm...port=objectonly
Abstract
IMPORTANCE:
Glucosinolates, a group of phytochemicals abundant in cruciferous vegetables, may have cardioprotective properties. However, no prospective study has evaluated the association of intake of glucosinolates with the risk of coronary heart disease (CHD).
OBJECTIVE:
The objective of the study was to evaluate the association between the intake of glucosinolates and incident CHD in US men and women.
DESIGN:
Prospective longitudinal cohort study.
SETTING:
Health professionals in the USA.
PARTICIPANTS:
We followed 74,241 women in the Nurses' Health Study (NHS; 1984-2012), 94,163 women in the NHSII (1991-2013), and 42,170 men in the Health Professionals Follow-Up Study (1986-2012), who were free of cardiovascular disease and cancer at baseline.
EXPOSURE:
Glucosinolate intake was assessed using validated semi-quantitative food frequency questionnaires at baseline and updated every 2-4 years during follow-up.
MAIN OUTCOME MEASURES:
Incident cases of CHD were confirmed by medical record review.
RESULTS:
During 4,824,001 person-years of follow-up, 8,010 cases of CHD were identified in the three cohorts. After adjustment for major lifestyle and dietary risk factors of CHD, weak but significantly positive associations were observed for glucosinolates with CHD risk when comparing the top with bottom quintiles (hazard ratio {HR}:1.09; 95% CI: 1.01, 1.17; Ptrend<0.001). Higher intakes of three major subtypes of glucosinolates were consistently associated with a higher CHD risk, although the association for indolylglucosinolate did not achieve statistical significance. Regarding cruciferous vegetable intake, participants who consumed one or more servings per week of Brussels sprouts (HR: 1.16; 95% CI: 1.06, 1.26; P<0.001) and cabbage (HR: 1.09; 95% CI: 1.02, 1.17; P=0.009) had a significantly higher CHD risk than those who consumed these cruciferous vegetables less than once per month.
CONCLUSION AND RELEVANCE:
In these three prospective cohort studies, dietary glucosinolate intake was associated with a slightly higher risk of CHD in US adults. These results warrant replications in further studies including biomarker-based studies. Further studies are needed to confirm these findings and elucidate mechanistic pathways that may underlie these associations.
KEYWORDS:
coronary heart disease; cruciferous vegetable; diet; glucosinolate

---

 

I don't find a 1.16 hazard ratio particularly compelling nor do I place a lot of faith in food frequency questionnaires but evidence of this caliber informs many of our nutritional beliefs.

[Gordo]

I wonder what the result would be if you excluded all who were overweight?

[Matt]

How do most people eat their cruciferous vegetables in the US?  Here, they are usually eaten after being boiled for about 30-45 minutes, and eaten alongside heaps of gravy and processed red meat. 

 

Cruciferous vegetable consumption is associated with a reduced risk of total and cardiovascular disease mortality.

https://www.ncbi.nlm.nih.gov/pubmed/21593509

 

Cruciferous vegetable intake and mortality in middle-aged adults: A prospective cohort study.

https://www.ncbi.nlm.nih.gov/pubmed/29739681

 

 

Cruciferous and Total Vegetable Intakes Are Inversely Associated With Subclinical Atherosclerosis in Older Adult Women.

For each 10 g/d higher in cruciferous vegetable intake, there was an associated 0.006 mm (0.8%) lower mean CCA-IMT (P<0.01) and 0.007 mm (0.8%) lower maximum CCA-IMT (P<0.01). Other vegetable types were not associated with CCA-IMT (P>0.05). No associations were observed between vegetables and plaque severity (P>0.05).

https://www.ncbi.nlm.nih.gov/pubmed/29618474

[Todd Allen]

Matt. thanks for linking to those papers.  They are examples of studies with similarly weak results based on food questionnaires.

 

I agree with you and Gordo raising possibilities of confounders but the risks of confounders exist in all of these observational type studies whether we like the results or not.

[Sibiriak]

A single study, only "slightly higher" apparent risk, weak association, "further studies needed to confirm",  no causal mechanisms elucidated,  crucial glucosinolate bioavailability issues  excluded, multiple possible explanations, focus only on CHD  (strong evidence exists for cruciferous anti-cancer effects).

 

evidence of this caliber informs many of our nutritional beliefs.

 

Not mine.  I have massively higher evidentiary standards.

[Sibiriak]

From the study:

 

In the sensitivity analyses, adjustment for other major dietary factors instead of the modified AHEI score slightly attenuated the HR (95% CI) per SD increment of glucosinolate intake for CHD to 1.02 (0.99, 1.04) (P=0.15)

 

Higher cruciferous vegetable consumption was non-significantly associated with an increased risk of CHD.

[Todd Allen]

Good catch Sibiriak.  Funny how these statements can co-exist in the same paper:

 

participants who consumed one or more servings per week of Brussels sprouts (HR: 1.16; 95% CI: 1.06, 1.26; P<0.001) and cabbage (HR: 1.09; 95% CI: 1.02, 1.17; P=0.009) had a significantly higher CHD risk than those who consumed these cruciferous vegetables less than once per month.

 

 

Higher cruciferous vegetable consumption was non-significantly associated with an increased risk of CHD.

[Saul]

 

Thanks Matt.

 

I consider the evidence that you present consistent with themany previous studies that have been done on this topic,

As Sibiriac points out, the evidence in the contridictory study is week

 

-- Saul

 

P.S.: My daily breakfast consists of ca. 1 pound of raw Nappa cabbage, plus a large pot of home brewed Chinese white tea.