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According to a California State University article Milk new symbol of hate?:

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The federal endorsement of milk in American diets contributes to the problem by uncritically pushing people to drink milk, despite the potential detriment it has on non-white people’s health.

Our current federal dietary guidelines urge people to drink three cups of milk a day, according to the 2015-2020 Dietary Guidelines for Americans. The main health benefit of milk is to guard against osteoporosis, a disease that weakens your bones — hence the “stronger bones” rhetoric. While this is a very practical health benefit, osteoporosis affects Africans at a significantly lower rate than it does most Americans, according to an article on Mother Jones.

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The Mother Jones article states that not only is milk non-beneficial to Africans, but following the guidelines may actually be detrimental to their health. There is a strong correlation to calcium consumption and an increased risk of prostate cancer, unproportionally affecting African men. Furthermore, both black children and adults generally secrete less calcium on a daily basis than white people, making them less dependent upon milk.

Is it true that African-Americans are being disproportionally harmed by being told by the government to drink milk?

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DavePhD
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    @DavePhD Gotcha; I'll write up an answer. Would you prefer a focus on the general claim that the milk recommendation is bad for black Americans, or specifically an analysis of the arguments given in the linked article? – Nat Mar 17 '17 at 17:46
  • @Nat mostly I'm interested in the part about "a strong correlation to calcium consumption and an increased risk of prostate cancer, unproportionally affecting African men. Furthermore, both black children and adults generally secrete less calcium on a daily basis than white people, making them less dependent upon milk" – DavePhD Mar 17 '17 at 18:05
  • To everyone asking if is a serious question: I recommend to assume good intent & just vote down if you don't find this useful. I think that fits the guidelines pretty well also. –  Mar 17 '17 at 21:25
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    I have deleted a lot of comments (many expressing political opinions) about the seriousness of the question. The OP has shown that the claim has been taken seriously. Please don't focus on whether you agree with the political opinion of the referenced article, and focus on whether the selected claims are supported by empirical evidence. – Oddthinking Mar 17 '17 at 23:18
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    There are two claims here: whether drinking milk is worse for blacks than whites and whether the advice to drink milk is racist. The first requires simple epidemiological evidence; the second requires a great deal more than that including *intent*. – matt_black Mar 17 '17 at 23:41
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    @matt_black I'm just asking about whether the government milk consumption advice is disproportionately bad for black. – DavePhD Mar 18 '17 at 00:04
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    You might note that African-Americans are not the same as Africans. Most have at least some European ancestry, so any study done on Africans may or may not carry over. – jamesqf Mar 18 '17 at 03:57
  • This is not a *"California State University article"*, in the sense of peer-reviewed publication; and the author's confusing 'Africans' with 'African-Americans' illustrates how sloppy the article is. It's an article from a journalist at [Daily 49er](https://en.wikipedia.org/wiki/California_State_University,_Long_Beach#Campus_publications), one of three student publications at CSU Long Beach, covering an article in MotherJones, which covered [a publication in BoneKEyy, an offshoot of the journal Nature](https://www.nature.com/bonekeyreports/2016/160629/bonekey201630/full/bonekey201630.html) – smci Jul 09 '18 at 01:28

2 Answers2

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The article doesn't link to the Mother Jones article that spawned it, but it's here.

The article makes several points:

  1. Consuming dairy has to be done carefully by people who are lactose-intolerant (a condition more common among blacks and Asians than among whites)
  2. Dairy doesn't reduce the incidence of osteoporosis, which blacks are less likely to get.
  3. Calcium increases the chance of prostate cancer.

So far as I can tell, the last two are completely unproven. Even the research the Mother Jones article cites says

whether specific dairy products or calcium sources are associated with risk is unclear.

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    The study that suggested that there hypothetically might be a cancer link was published in 2012, decades after the government started pushing milk. Which just proves time machines. – Nat Mar 17 '17 at 17:18
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    Lactose intolerance is common in some populations (like blacks) but not in children. People (regardless of race) are born able to drink milk but *some* lose this ability as they get older. Adults are usually able to judge whether they are intolerant and I doubt that federal guidelines would much impact their choices. – matt_black Mar 17 '17 at 23:37
  • Let us [continue this discussion in chat](http://chat.stackexchange.com/rooms/55558/discussion-between-wildcard-and-nat). – Wildcard Mar 18 '17 at 03:00
  • Point 2's first clause is wrongly paraphrased (and wrongly understood?) in this answer. The article doesn't confidently assert dairy doesn't reduce the incidence of osteoporosis: It spends a paragraph where that's mentioned as a possibility in one sentence, before moving on to the genetic-predisposition-to-retain-calcium argument with the phrase "more compelling" being used to introduce the latter. The most generous view the article might be according to the idea that dairy doesn't reduce osteoporosis is accepting it as a possibility, rather than making a confident truth claim that it is so. – mtraceur Mar 19 '17 at 06:08
  • @matt_black I was the other way round - I was intolerant but no longer am... – Tim Mar 19 '17 at 10:06
  • Malvolio, the government milk recommendations specifically address lactose intolerance. Page 23 here and cited appendix portions: https://health.gov/dietaryguidelines/2015/resources/2015-2020_Dietary_Guidelines.pdf I think your answer could be improved by including what the milk recommendation actually are. – DavePhD Mar 19 '17 at 22:00
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Generally agree with @Malvolio's answer, though to expand on a claim within the article as requested:

"a strong correlation to calcium consumption and an increased risk of prostate cancer, unproportionally affecting African men. Furthermore, both black children and adults generally secrete less calcium on a daily basis than white people, making them less dependent upon milk"

To support this, the article cites Dairy products, calcium, and prostate cancer risk: a systematic review and meta-analysis of cohort studies (2014), which claims in its abstract:

Dairy product and calcium intakes have been associated with increased prostate cancer risk, but whether specific dairy products or calcium sources are associated with risk is unclear.

From the conclusions of that article (emphasis added):

In conclusion, we showed increased risk of prostate cancer with intakes of total dairy, milk, cheese, low fat and skim milk combined, total calcium, dietary calcium, and dairy calcium but no association with supplemental calcium or nondairy calcium and an inverse association for whole milk. A positive association between supplemental calcium and fatal prostate cancer needs additional study. Diverging results for types of dairy products and sources of calcium suggest that other components of dairy than fat and calcium may increase prostate cancer risk. Additional prospective studies are needed on types of dairy products and various sources of calcium in relation to risk of subtypes of prostate cancer and, in particular, advanced and fatal cancers.

So, the claim that the calcium in milk causes prostate cancer doesn't appear to be supported by the article's cited study. Rather, the cited study claims:

  1. Increased whole milk consumption correlated with a lower rate of prostate cancer.

  2. Calcium intake does not appear to increase prostate cancer risk.

Addendum

Abstract 1777: Prostate cancer risk factor profiles in black and white men in the NIH-AARP Diet and Health Study is an abstract for a talk presented at the 2016 conference for the American Association of Cancer Research.

In this talk, the researchers discussed how nutrition may relate to differing rates of prostate cancer in non-Hispanic white men and black men. Their primary point appears to be that the factors that may contribute to prostate cancer may differ between whites and blacks.

Conclusions: Our data suggest that many factors thought to influence prostate cancer risk in predominantly non-Hispanic white populations explain only a small proportion of black male risk, or the black-white difference in risk. Dietary vitamin D intake, height, and alcohol consumption associations with prostate cancer risk may vary between black and white men.

This abstract doesn't mention calcium, though it does mention Vitamin D, also found in milk. Apparently the researchers found that Vitamin D may increase cancer risk for white men, but may decrease cancer risk for black men.

I'd stress that these correlations are highly speculative. For example, the 95% confidence intervals (CI) for Vitamin D's effect for blacks/whites overlaps. So, we're talking about very small, quite-possibly-non-existent effects.

But, if you take the numbers at face value, then Vitamin D may reduce prostate cancer risk in black men. This would seem to suggest that milk's less likely to cause cancer for black men than for white men, all else equal and, again, noting how incredibly small and dubious these alleged effects are.

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  • so does the study mentions blacks or Africans or African Americans at all? – DavePhD Mar 17 '17 at 18:57
  • @DavePhD Naw, it doesn't appear to directly mention blacks or Africans anywhere. Though in the introduction, it does have a paragraph talking about how prostate cancer rates are lower in other parts of the world, including Asia and Africa, leading to the suspicion that it may be correlated with regional points of difference. – Nat Mar 17 '17 at 19:06
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    @DavePhD The PDF's 31 pages, but the gist that I get from it's basically: "Prostate cancer rates vary significantly by geographical location. The variance appears to be related areas with more European influence. Since there's a suspicion that calcium intake may be the cause, we checked out dairy products. We found no evidence to support that calcium intake's actually the problem, though there's still obviously some sort of phenomena causing regional differences, so more research is needed." – Nat Mar 17 '17 at 19:10
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    @DavePhD It looks like they think that dairy products may be a culprit, though not due to the calcium that they contain. Also it's probably not specifically milk, since high consumption of whole milk was correlated with a reduced cancer rate. My impression's that their analytical methods aren't refined enough to pin down the actual problem; most of their results look like noise to me. – Nat Mar 17 '17 at 19:15
  • @DavePhD Updated the answer with a source that provides the most recent analysis on prostate cancer dietary causation for black American men that I've found. It looks like they found Vitamin D appears to provide a very small (and probably not significant) reduction in prostate cancer rates for black men, while calcium wasn't mentioned (presumably it's one of the things that they said was shown to be unrelated). Also, sorry to spam you - I'm a little too fascinated by how pop culture sees scientific studies. – Nat Mar 17 '17 at 22:45
  • Weird observation: It sounds like the biggest difference they found between blacks and whites was with regards to height. In white men, height doesn't have a significant impact on prostate cancer risk; however, for black men, shorter men appear to have a higher risk than taller men. That observation's _just barely_ within the 95% CI interval (and so, it's quite possibly just a statistical outlier). – Nat Mar 17 '17 at 22:51
  • Vitamin D is artificially added to milk, so I guess a related issue is whether or not blacks are being harmed by the addition of vitamin D to milk. – DavePhD Mar 18 '17 at 12:19
  • @DavePhD The above study claims that Vitamin D may be reducing prostate cancer in black American men. Still, I dunno about people looking too far into this stuff; the methods that these studies use are so incredibly noisy and flawed that it may be overly generous to call them "evidence". Personally I love all scientific studies regardless of their limitations, _but_ I think that 95%+ of the population misunderstands these studies as meaning more than they do. The level of noise is so high that they're essentially meaningless in most cases. – Nat Mar 18 '17 at 15:13
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    @DavePhD For example, I wouldn't recommend that black men change their milk consumption habits based on these studies. Not only did the studies not suggest this was beneficial, but even if they had, the evidence is so overwhelmingly weak that it boarders on superstition. It'd be better for black men to live life as they want, enjoying milk if they want it, rather than being paralyzed by a fear of an effect that's probably not even there in the first place. – Nat Mar 18 '17 at 15:15
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    It's worth mentioning that statistical studies of prostate cancer specifically are even noisier than (already noisy) studies of risks for other types of cancer, because it's relatively very common to live with prostate cancer unaware, and then die of something else (its age profile is among the oldest of any cance, very common, and it generally takes a long time to have health impacts). Anything that correlates with longer life or higher likelihood of taking tests like PSA has a *huge*, unusually hard to mitigate confounding effect. – user56reinstatemonica8 Sep 18 '19 at 22:38