Tag: public policy

Does COVID vaccination or infection generate more social benefit?

The US (and many other) governments currently deploy considerable resources and effort to increase COVID-19 vaccination rates above whatever rate might occur if left to spontaneous provider and individual decisions. Compared to support for other health interventions, the magnitude of government support for C-19 vaccination is unprecedented. 

The rationale for this support is the societal benefit produced by the vaccinations. Plainly speaking, in addition to whatever personal health benefit I get from a C-19 vaccination, it also reduces my likelihood of spreading the virus for some period of time. The latter is the societal benefit, or in economics-speak, the positive externality that constitutes a rational for government action to increase the vaccination rate.*

Current COVID vaccination policy presumes this societal benefit from individuals getting vaccinated is sizable. The societal benefit production process can be understood thus: a virus-naïve person is vaccinated and thereby acquires some immunity, rendering him a non-spreader**. He thereby contributes to the proportion of immune or non-spreading people in the community, and renders interpersonal interaction in the community “safer” for other people. In particular, high risk people who are self-isolating gain because at some higher level of safety – they are able to return to normal social interaction.

If this mechanism of producing a societal benefit is indeed the positive externality justifying unprecedented state support to induce individuals to get vaccinated, then, here is what perplexes me.

Let’s assume the naïve person does not get vaccinated, but instead gets infected.  Then, he either dies and is gone from the community; or, he recovers and has acquired natural immunity. Compared to the person getting vaccinated, this transformation puts him in the nonspreader category for a longer period of time, and also keeps him in that category more reliably in the face of virus mutation. For the high risk person, the community’s “safeness” depends on the proportion of nonspreaders in the population on a continuous, sustained basis. Thus, they obtain more societal benefit when someone gets infected compared to getting vaccinated – because the recovered person maintains their nonspreader status longer (& more reliably) than a vaccinated person.***

I realize additional potential externality issues may arise here. See this awesome paper Leeson, P. T. and L. Rouanet (2021). “Externality and COVID-19.” Southern Economic Journal 87(4): 1107-1118 for a more refined elaboration. However, the production of the “community safeness level augmentation” positive externality that I outline here does seem to be the one that dominates COVID vaccination policy discourse. That is, government support (subsidies to vax development, subsidies to vax delivery, marketing and other communications to persuade members of the public to get vaccinated; coercive tools such as mandates & passport regimes to establish burdens and barriers in daily life that incentivize unvaccinated people to get vaccinated) appears to be predicated on this type of positive externality being significant.

Yet, if my logic is correct, people highly concerned with reducing their probability of getting infected – gain more benefit from people getting infected compared to getting vaccinated. If this is correct, then the unprecedented government support to increase vaccination rates is, to put it politely, unmerited.

I welcome comments elaborating what I am missing or what is wrong with my logic on this.

* Note that for an intervention with significant positive externalities to merit public support also requires that the intervention be cost effective and spontaneous private demand be inadequate. See Musgrove (1999) Public spending on health care: how are different criteria related? Health Policy.  

**I realize that it would be more accurate to refer to the person’s status as “relatively unlikely spreader”.

*** The calculus is different for vaccinations leading to eradication or elimination.  For viruses that are susceptible to eradication or elimination, achieving a high proportion of nonspreaders at a single point in time could conceivably end transmission and exposure risk for a very long period of time or even permanently. In that case, the positive externality of transforming a large proportion of the community into nonspreaders via vaccination would be dramatically higher than is the case here.

The market for health system analysis – the most broken market of them all

You’d think I’d be accustomed by now to famous pundits selling their bad health systems analysis from their large soapboxes. The truth is, I still get annoyed. Atul Gawande’s 2009 New Yorker piece – “The Cost Conundrum” was a memorable instance. It was a beautifully written and highly influential piece of policy advocacy. I’m not exaggerating when I say “highly influential”; President Obama was clearly taken with Gawande’s findings (see this 2009 speech). And, now we know (from this StatNews piece) the genesis of Gawande’s recent selection by Amazon, Berkshire Hathaway and JPMorgan Chase to lead their new cost-cutting disruptive healthcare venture was the same 2009 article. Gawande revealed the backstory in an interview at the Aspen Ideas Festival. Evidently the article so impressed Charlie Munger, Warren Buffett’s right-hand man, that Munger sent an unsolicited check in the mail to support Gawande’s work. One thing led to another and Atul Gawande got the job. Thus, I feel it is not inappropriate to point out that Gawande’s piece was WRONG WRONG WRONG in its analytics, findings and recommendations. Atul Gawande is probably a great surgeon and he’s surely a brilliant writer. One thing he is not is a health system expert.


In the New Yorker piece Gawande laid out what was driving US health care cost growth, and what US policymakers should do to contain it. In the piece he compares how much it cost to treat Medicare patients across “local health systems”. By scrutinizing the practices of “low cost” versus “high-cost” providers, he determined that policymakers can reduce costs in the US healthcare system by spreading the practices of the “low-cost” group. Here’s the rub. Gawande was looking only at costs for Medicare patients; that is, he was looking only at the healthcare services market segment within which prices are regulated by Medicare. This leaves out what is going on with the (larger) private insurance market. There is no reason to think that insights from the Medicare segment would apply to the whole set of delivery activities at the provider or provider network level. And, in fact, once someone checked, it turned out that the Medicare patterns look very different from those of private insurance.

MedCare vs priv costs us health

If he submitted his piece in my (admittedly, not-yet-existent) course on comparative health systems, I’d make him review the readings on segmented healthcare delivery systems and do it over. Unfortunately, he submitted it to a New Yorker editor – and thousands upon thousands of smart people learned his erroneous insights. Including, evidently, the US president and Berkshire Hathaway’s Charlie Munger.


An excellent piece in the NYTimes in 2015 – “The Experts Were Wrong” [also the source of the map graphic] drew on the work of Zack Cooper and others and explained the error in Gawande’s logic. NB: The link to Cooper’s work on the NYTimes site does not work – here is a working link. The insights from this analysis suggest that, to constrain health care costs, the  US should strengthen anti-monopoly regulation and pursue (much) broader price regulation. This work merits the attention that Gawande’s piece does not.

What will UK health officials do with all that excess demand?

Ever growing numbers of drug_shortageUK citizens are turning to private, self-paid, health care in the UK.

Mark Hellowell’s excellent piece “How the NHS will die” examines the forces at work, and ponders what actions may be taken to resolve this ‘excess demand’ problem. When the problem manifested in the late 1990s, UK officials ultimately resolved it with 10 years of public expenditure increases. Few predict public expenditure increases sufficient to resolve the problem will be forthcoming this time around.

Health officials invariably pursue efficiency gains to close such gaps. Efforts to do just that in outpatient drug spending, however, appear to be rebounding with a vengeance – to eat up ever larger chunks of the healthcare budget. For much of the past year, the Department of Health has been forced to resolve widespread drug shortages with month-to-month agreements to reimburse pharmacies at prices much higher than the official NHS tariffs. The Times put the extra costs for April – November 2017 at ₤200M. Ben Goldacre and co at Oxford give a tally through December of ₤285M. And, the unpredictable reimbursement of higher-than-official prices works more as a band-aid than a solution, since the shortages don’t appear to be diminishing.

Am I being too pessimistic? Are promising developments underway that I’m missing? Silver linings to accompany the gray cloud?

Updating practitioners as knowledge changes: the (discouraging) case of dietitians

I’ve become increasingly interested in the mechanisms through which health systems bring about practice changes among frontline providers. Pharmaceutical companies appear to do much of the work to reach and educate providers, if the practice change involves deploying a new pharmaceutical product. For the many other changes, I’ve yet to identify any approach which reliably and rapidly works across health systems. Health systems rely heavily on practitioner retirement and new entry – where the new entrants are educated on the new practice in their professional education. As the rate of medical knowledge accumulation accelerates, dissatisfaction with existing mechanisms is sure to grow.


Among medical knowledge domains, nutrition science has experienced relatively rapid change in the past 15 years. Naturally, this makes me curious about dietitians. How is the profession dealing with the changes? More to the point (for those of us interested in health systems): how well are different countries’ mechanisms for deploying practice change responding to this particular challenge?


A July 2017 paper by McArdle et al in the Journal of Human Nutrition and Dietetics presented some alarming answers to this question in the UK. McArdle and co-authors studied dietitians’ practice – focusing on what they advise diabetic patients with regard to carbohydrate consumption. NB: this is a domain where the appropriate advice has changed substantially in the past few years; in a nutshell, dietitians should be advising carbohydrate restriction.


The inestimable Zoe Harcombe synthesized the key findings thus:

This article shows that dietitians generally are confident in their advice – diabetes specialists especially so. Yet, fewer than one third (29.4%) of dietitians would recommend carbohydrate restriction even 50% of the time. More, (32.2%), would never, or hardly ever, recommend carb restriction. In the uncommon circumstances when carb restriction is supported, 92% of dietitians would advise type 2 diabetic patients to consume more than 30% of their total energy in the form of carbohydrate. Only 1 in 320 would advise the therapeutic level of carbohydrate for the treatment of type 2 diabetes.

dietitian old photo
Let me just check my class notes…..

Health services research regularly confirms how difficult it is to change the practice of doctors. Apparently this applies to dietitians as well. Given how many people are suffering with diabetes, I’d say we can’t afford to rely on the “wait for retirement” mechanism to work.

Take time to think: are you focusing your efforts to achieve public policy goals in the right place?

So much that I’ve learned, I learned from conversations with taxi drivers. The following exchange took place in Georgetown, Guyana’s capital. The same driver had driven me to the Ministry of Health four days running, and our conversation had broadened and deepened a bit.


 Taxi driver: So, what was it you said you are doing here in Georgetown again?

Me: Working to identify actions and develop plans to strengthen your health system.

Taxi driver: (quizzical look in rearview mirror)

Me: We want to find ways to improve people’s health, and figure out which ones to pursue and how. And then…make that happen.

Taxi driver: Uh huh. So, why do you spend all your time talking to those folks (nod in general direction of Ministry of Health building)?

Me: ummmm.


I eventually came up with some reply, no doubt. But the effort to do so got me thinking about how we health policy folks make decisions about where we focus our attention and efforts. And, I realized that we often do so unthinkingly. We go where we go by habit as much as anything. Yet, over the years, I’ve learned that where you focus your attention and effort is a critically important decision.


I was reminded of this when I read this recent editorial Public Health Policies: Go Local! by David Bishai, Shannon Frattaroli, and Keshia M. Pollack, in the American Journal of Public Health, arguing that the US public health community should do just such a rethink. Currently, they focus the majority of their attention on the nation level. Yet,

the bulk of the money and the decisions that drive the health of the public

remain in the hands and wallets of the people and their local communities.

They note that local public health policies can make profound contributions to most of the health goals we pursue, including goals to reduce health disparities. And, these efforts can make progress even in the face of gridlock and political dysfunction on the national level.

As my Guyanan taxi driver could likely have told you:

Most of what keeps populations healthy happens in their homes, cars, communities, schools, and workplaces.


What makes people sick are ideas, behaviors, chemicals, physical energy, and microbes that get close enough to penetrate the body. If you got a cold this year, you got it from somebody in the same room. Whiplash? The shockwave came from a bumper a few feet away. Hangover? Your friends may have poured and clinked the glass that gave it to you.

And, local and city policies and community level efforts can strongly influence these things. In fact,

(P)ublic health is also practiced by workplaces, neighborhood associations, schools, hospitals, health insurers, and many others with resources of time, money, and energy that dwarf national budgets for public health.

If you need more convincing of the virtues of focusing attention on the local level, Bishai et al point out that some US communities achieve outcomes rivaling those of world leaders (I’m looking at you Japan and Singapore). These outcomes depend on many factors besides public health and community efforts of course; nevertheless, spreading what nation-leading communities are doing with their public health spending, policies and activities could go a long way to closing those gaps.

What is known and practiced in the best-performing communities must be spread throughout the country.

Given that these efforts are not hamstrung by dysfunction in the national level political apparatus, I could not agree more with Bishai et al’s closing plea:

A renewed emphasis of the public health community on local action is long overdue.

I highly recommend you read the editorial; it is, alas, gated. I’m happy to email it to you.

Disheartened by the protests

Given the continuous flow of bad news re the Trump administration and Congress, I understand why many of my friends were encouraged by the women’s marches. Me though…I am not feeling so encouraged.


Reading about the protests, I thought about the large numbers of Americans who voted for Trump and the Republicans in this past election. I wondered: how did the protests and related photos and media coverage look to them? Did the protests spark any reconsideration of their support? Doubtless many of these voters are die-hard Republican voters – and efforts to mobilize them, to persuade them to join the opposition will bear no fruit. But what about the more ‘marginal voters’? What about Peggy Sue in Iowa who voted for Trump with reservations? Or her cousin, Bobby Joe in Wisconsin who votes sometimes for Democrats and sometimes for Republican candidates, but went with the Republican candidates in this election?


There are many issues upon which Trump and co. should be opposed; yet the protests manifested a highly culture-focused opposition. Will this focus appeal to the many voters who weren’t sufficiently put off by the cultural elements of Trump’s campaign?  Think of the  many white women who heard Trumps disrespectful comments regarding women, yet still voted for him.


I realize that the opposition will not consist of protests only – and protests naturally tend toward cultural issues. But, I fear the protests signaled the likely focus and tone of their future efforts. And, it’s hard to imagine the Trump opposition will appeal very much to Peggy Sue or Bobby Joe unless they broaden their topical focus and dial down the shriller voices on issues like abortion.


Most Americans have mixed feelings regarding policies toward abortion; yet, the protests gave the impression that those who lead the opposition to Trump will tolerate no constraints on access to abortion. In fact, they won’t tolerate people who feel differently on this point. NB. March leaders blocked participation by pro-life women’s groups.  An opposition that appeals only to the relatively small proportion of Americans who hold these views on abortion-related policies is unlikely to persuade Peggy Sue or her cousin to cross over.


Our country’s social gains re racism, homophobia and the like are precious. Perhaps Americans are taking these gains too much for granted; we clearly need to be vigilant. Yet, I do worry that Peggy Sue and Bobby Joe may not be mobilized by an opposition movement that puts combatting racism (and other -isms) at the top of their agenda.


Please understand, this is not a statement of my positions, or preference orderings. I’m pondering the possible appeal of these positions to hypothetical people who live well outside the coastal-cultural-elite bubble in which I reside. I’d love to hear what others think – whether they dwell inside or outside the bubble 😉


Pakistan’s unusually useful education report card

Alif Ailaan just published a report ranking Pakistan’s districts according to how well they are performing in education. They collect information not only on performance but also policies and practices, and they do so annually. The data can be used to illuminate policies and practices which distinguish the education leaders from the laggards. Importantly, the “better” policies and practices are demonstrably relevant and feasible in the Pakistani context.  Other types of benchmarking and report cards (e.g. cross country, single point-in-time) very rarely yield such useful insights. I won’t elaborate here as to why this is so. If it’s not obvious, I suggest you google “complex systems” and “external validity”. I commend Alif Ailaan staff, and their funder, the UK Department for International Development, for this excellent work. I am perplexed as to why it is so rare in both health and education. HT to Harry Patrinos.

The high cost of talking down to policy practitioners

Poor understanding of how markets work is a big stumbling block in developing country health policy making. I have seen the stumbling block in action, and concluded that it is an urgent priority to provide accessible knowledge resources and learning opportunities in this area. There are few good resources and fewer learning opportunities for policy practitioners working in, and on, developing countries.

So, I was delighted when I discovered USAID’s Healthy Markets for Global Health: A Market Shaping Primer. The Primer aims to provide developing country policy practitioners with some essential, practical knowledge about markets and forming policies to influence markets. I stayed up way past my bedtime pouring over it. And….I got a headache. The authors decided to use a unique definition of a market. They implicitly defined a market as: the set of actors making decisions related to production, distribution, and delivery of “global health products”. Now, whatever this “thing” is, it is decidedly not a market. There are different ways of saying it, but a market consists of the interaction between all the buyers seeking something and all the sellers from whom they may get it. The Primer team opted for their simpler alternative, presumably, to make the Primer’s content more accessible to practitioners.

A brief aside: I believe the quality of health policy in developing countries is undermined, considerably, by what I think of as “the wall”. “The wall” is my shorthand for the observably low interaction between the developing country health policy and ops research community and the developed country health policy and ops research community. Let’s leave aside, for the moment, the size of “the wall” and its foundations. I believe most of us believe that more interaction between these two worlds or “tribes” is better; we need more interaction, more communication, and, more engagement across these tribal boundaries. I believe both tribes would benefit. Given the paucity of content on the topic of markets in the health sector in the developing country literature, in this domain, more communication would especially benefit the developing country policy practitioner tribe.

And, you know what doesn’t help? Making up, and disseminating, special definitions for core concepts, like, oh…say…markets.

Perhaps you think using different words for core concepts, and different concepts for oft-used words, is but a minor offense.

Having sat through many, long, frustrating, discussions on public-private partnerships in the health sector, I must disagree. In my experience, when members of the developing country policy practitioner tribe try to engage in, and learn about, these issues, their ability to do so is greatly diminished when the vast majority of the existing knowledge is made inaccessible, or even impenetrable, because of “translation” problems. Check out this ppt – my small contribution to a Rosetta Stone for PPP discussions across tribal boundaries.

My point is this: teaching developing country policy practitioners about markets is a worthy aim. Making the content accessible is important. However, teaching practitioners a unique-in-the-world definition for market is a bad call. All the learners reached will hence forth find the vast body of knowledge on the topic of markets even less accessible and useful than if they knew nothing at all.

Perhaps the primer-makers believe they have re-packaged (“translated”) all the knowledge about markets the target learners will ever need; in which case, increasing the height of “the wall” between them and the rest of the world does no harm.  If so, I disagree.

What do you think?

“Better Practice” Regulation Can Work: Lessons from Tanzania’s Accredited Drug Dispensing Outlets initiative.

“The quality of care in the private sector is unreliable. The regulatory framework needs to be strengthened.” How many times have you read that? Or, “the regulatory agency needs to do more to enforce the rules”? Do you recall any successes along these lines? No? Yeah, me neither. Until I learned about Tanzania’s Accredited Drug Dispensing Outlet (ADDO) initiative.

Drugshops constitute an important part of the primary care system in many developing countries. They provide a lot of care, especially in rural areas, especially to the poor. They provide care for a lot of illnesses which are especially important to children. They typically “practice” way beyond their skills. The quality is not reliable quality. However, they are not going away. Generally, little is done to address this cadre. Invariably, regulations exist that prohibit them from doing more than dispense a “safe” lists of medicines. They don’t comply. And if they did, diabetics who live in rural Ghana would have to travel 1,2, even 6 hours to get their insulin. Same for Nigeria, etc. Some donor-disease projects have sought to improve their practice in one area or another e.g. family planning, malaria. Education activities targeting drugs shops and their customers usually succeed in improving practice (Wafula Goodman 2011). But none have been done at a large scale, and since the better practice often requires drugshops to lose income, sustainability is questionable.

Then comes the ADDO initiative. ADDO initiative demonstrated that with a “better practice” approach to regulation it is possible to reach the entire cadre of drug shops, to change their practice for the better, and to bring them in to play a considered role in a country’s primary care system. The ADDO experience showed that by using this approach to engaging private providers, it is possible to recover regulation as a social policy instrument.

Missing-in-action: regulation policy instrument. In most countries, drugshops daily practices go well beyond what regulation permits. And this gap is a big (big) problem. Why? Because it means that policymakers no longer have regulation as an instrument to influence behavior.  Let me explain.

Keep in mind, outside of police states, most citizens’ rule-compliance behavior is voluntary – it is not done in fear that doing otherwise may lead to being caught and punished. Buy-in to the rules is likewise a very important element of health practitioner and facilities compliance in all well-functioning health systems (Hort et al 2013). Practitioners’ associations’ involvement in developing the rules, and the responsibility that take in bringing along their members towards compliant behavior is an essential ingredient. And, with respect to drugshops in many developing countries, they are so many, and so widely geographically dispersed, virtually all compliance with rules will have to be achieved through practitioners’ voluntary decisions.

The large practice-vs-regulation gap in most countries tells us that the content of existing rules is not seen as legitimate. Neither the individuals nor their colleagues nor their association feels “it is the right thing to do” to follow all the provisions in the rules. They feel neither intrinsic nor social pressure to comply.  Hence, policymakers can pull on the regulation policy “lever” all they want, but nothing happens, because it is no longer attached to the practitioner cadre’s domain.

Tanzania’s ADDO initiative showed it is possible to recover regulation as a policy instrument. It’s not easy. But it’s doable. And it is doable – even for this hard-to-reach, but hugely important practitioner cadre.


 How did they do it? From discussions in a recent workshop on drugshops and pharmacies in developing countries hosted by PATH, my understanding of the process is:


1.      “Start where you are” principle. Professionals involved with ADDO emphasized how much time and effort they devoted to characterizing what was going on with the drugshops at the beginning. Who was using them? For what? What did drugshops do? Really? What medicines did they sell? With what advice? Where did they get their medicines? This is a core practice of the “whole systems approach” to improving service delivery, which emphasizes starting off with mapping existing provision capacity and utilization patterns to identify providers/ services which may otherwise be overlooked. See Stevenson 2001.

2.      Inclusive policy dialogue. They started and sustained dialogue between practitioner representatives, regulators and other key stakeholders.

3.      Negotiate to a middleground. They negotiated their way to a new scope of practice – in consultation and sustained interaction between practitioner representatives and technical experts and other politically important stakeholders (e.g. pharmacists) which constituted a better, safer scope of practice. The scope was more limited than their actual, current practices, but broader than the scope permitted in current regulations. Drugshop representatives thought their members could comply without undermining their ability to operate as sustainable businesses.

4.      Elaborate the policy element of the new arrangement. In Tanzania they settled on using an accreditation regulatory instrument. This is  a regulatory instrument where providers’ participation is voluntary, and participation is motivated at least partly by improvement in market position (e.g. more customers because accreditation “mark” is valued by would-be clients).

5.      Pilot – they tested the new parameters for the initiative (scope of practice, role of practitioner assn, other implementation issues).

6.      Review and adapt.  Officials reviewed the pilot implementation experience and results in consultation with drugshop representatives and other stakeholders; and, together, they agreed on adapted parameters based on those insights.

7.      Strategic communication. They made conscious efforts to get buy-in from key public officials (e.g. parliamentarians, regulatory agency officials).

8.      Scale- up. With all this in place, they moved to scale up and roll out the initiative.

Initiatives to improve services in developed countries virtually always exhibit these features; they “start where they are”, they adapt the strategy as they go. And, critically, policy formulation and implementation is inclusive of those providers whose behavior and activities are targeted. Such efforts are rarely inclusive in developing countries, especially where the relevant providers are private. Surender et al noted the glaring omission when they compared South Africa’s approach to reforming primary care to that taken in developed countries. The low influence of regulations and low impact of regulatory efforts in developing countries surely derives significantly from this non-consultative, exclusive approach to policy. My take on the ADDO initiative is that it is important because it illustrates that if health policymakers shift to “better practice” approaches to regulation, they can reestablish regulation as a functioning instrument to exercise stewardship. And, they can do so even for drugshops – which constitute a critically important but hard-to-engage part of many countries’ primary care systems.

Time to rethink fat consumption, if you haven’t already

A study “Association of Dietary, Circulating, and Supplement Fatty Acids With Coronary Risk; A Systematic Review and Meta-analysis” published March 18 in the Annals of Internal Medicine should be the “nail in the coffin” of the lipid hypothesis (linking saturated fat consumption to coronary heart risk). I want to help out, to hammer one tiny nail in the coffin of this zombie idea. Herewith, my hammer swings.

The study is a systematic review of all available evidence on the lipid hypothesis, including observational studies, prospective cohort studies and RCTs. Taken together, the evidence does not support any link between consuming saturated fat and coronary heart risk. Its “surprising” results have come up in several conversations this week; one friend (you know who you are) speculated that the research may have been funded by a nefarious, self-interested funder (the beef industry perhaps?). This is not the case – as you can see if you follow the link above.

My friends, and many others, are suspicious because the finding conflicts with so much existing evidence. Except, they do not; rather, the finding confirms the balance of existing evidence. The findings are at odds with current dietary guidelines and conventional wisdom. This is a very different issue altogether.

Since this issue has come up in several conversations, I want to lay out what I  discovered when I examined the evolution of the evidence for this hypothesis, as well as the evolution of dietary guidelines.

The origin of the lipid hypothesis lay in poor handling of then-available observational data. To wit, Ancel Keys’ Seven Countries Study (1980), which examined observational data on changes in fat consumption and heart disease levels of different countries. It was named for the seven countries that saw an increase in heart disease cases correspond with increased fat consumption; the study ignored considerable additional observational data that was available at the time – which, taken together, supported the linkage – but weakly. Nevertheless, Time magazine covers, and sadly, national dietary guidelines based on the findings followed.There have been many more observational studies since then. Taken together, their findings do not support the lipid hypothesis. Check out this excellent overview of the evidence.

The mechanism? The concern over fat gathered steam when studies showed that saturated fat increases LDL cholesterol — the bad cholesterol — the artery-clogging stuff. They assumed this increased the risk of heart disease. When further studies did not confirm saturated fat elevated coronary heart risk, researchers started to dig more deeply into the mechanism. They found the more important predictor of risk is the ratio a person has of LDL to HDL, the good cholesterol. Note, compared with carbohydrates, saturated fat can increase HDL and lower fat deposits in the blood called triglycerides, which, is protective against heart disease. Heck, even the American Heart Assn admits this. In fact, more recent studies, such as those examining the health effects of consuming full-fat dairy – see here and here, suggest there are health benefits from eating higher saturated fat diets.

Nor do subsequent prospective, cohort studies (e.g. Framingham) support the lipid hypothesis. See this systematic review Siri-Tarino, P. W., Sun, Q., Hu, F. B., & Krauss, R. M. (2010). Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. The American journal of clinical nutrition, 91(3), 535-546.  They foundno significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD”.

Many RCTs to measure the effects (in terms of fatal or non-fatal heart attacks) of saturated fat have been either inconclusive, poorly designed, or completely unsupportive of the hypothesis. A few such studies are (I could not find a systematic review of only RCTs):

  • Research committee. Low-fat diet in myocardial infarction. A controlled trial. The Lancet 1965;2:501-4.
  • Rose GA, Thomson WB, Williams RT. Corn oil in treatment of ischaemic heart disease. British Medical Journal 1965;i:1531-3.
  • Research committee to the medical research council. Controlled trial of soya-bean oil in myocardial infarction. The Lancet 1968;ii:693-700.
  • Dayton S, and others. A controlled clinical trial of a diet high in unsaturated fat in preventing complications of atherosclerosis. Circulation 1969;40(suppl 2):1-63.
  • Leren P. The effect of plasma cholesterol lowering diet in male survivors of myocardial infarction. A controlled clinical trial. Acta Medica Scandinavica 1966;suppl 466:1-92.
  • Woodhill JM, and others. Low fat, low cholesterol diet in secondary prevention of coronary heart disease. Adv Exp Med Biol 1978;109:317-30.
  • Burr ML, and others. Effects of changes in fat, fish, and fibre intakes on death and myocardial reinfarction: diet and reinfarction trial (DART). The Lancet 1989;2:757-61.
  • Frantz ID, and others. Test of effect of lipid lowering by diet on cardiovascular risk. The Minnesota Coronary Survey. Arteriosclerosis 1989;9:129-35.

This brings me back to the just-published systematic review of the available evidence from all three methods (observational, prospective cohorts; and, RCTs) Chowdhury, R., S. Warnakula, et al. (2014). “Association of Dietary, Circulating, and Supplement Fatty Acids With Coronary Risk: A Systematic Review and Meta-analysis.” Ann Intern Med 160(6): 398-406.

Which, unsurprisingly, found that “current evidence does not clearly support cardiovascular guidelines that encourage high consumption of polyunsaturated fatty acids and low consumption of total saturated fats”.

Let us hope government guidelines will finally be changed to reflect the evidence. We can’t take such a change for granted though. The folks involved with developing dietary guidelines have been ignoring the evidence they are wrong for quite awhile (see here and here).

I am not giving dietary advice. I am encouraging my many econometrically literate friends to take a look at the evidence themselves. Like me, I think you will be surprised what you find.