Carbohydrates, not animal fats, linked to heart disease across 42 European countries

A study of 42 European countries found lower cardiovascular disease and mortality among countries that consumed more fats and animal protein. Higher cardiovascular mortality was linked to carbohydrate consumption. Another nail in the coffin for the diet-heart hypothesis?

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Cholesterol and CVD – How reliable are the risk calculators?

The red line shows the expected number of 10yr fatal CVD deaths predicted by SCORE. The dots represent the actual percentage of deaths observed in a Danish population [Mortensen et al, Jun 2015, European Heart Journal]

A recent study among the population of Denmark has found that the SCORE (Systematic COronary Risk Evaluation) model for predicting CVD deaths in low risk European countries (see our previous post) overestimates 10 year risk of death compared to what is actually observed by no less than 500% (4.9-fold in men and by 5.5-fold in women).

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Cholesterol and CVD – putting the risks into perspective

“Heart disease risk”, “raised cholesterol”, “Statins” – these six words are guaranteed to strike fear into almost anyone who has been unfortunate enough to be cursed by their local witch doctor wielding these hexed mantras. For years the public psyche has been hyper-sensitised to these terms through incessant media reporting and public health messages. Continue reading

How can bitter foods be good for us when they taste so bad? – Resolving the paradox

Laying out the problem

Our recent post on bitters, left me with a lot of questions.

If bitter tastes indicate the presence of toxins and thereby help us avoid poisonous foods, why do they stimulate such positive physiological responses? Why would some of those responses protect us from metabolic diseases like diabetes and cancer? If bitter taste is merely a warning to avoid a particular food, then why do many traditions revere bitter foods? How do we explain why adults develop a taste for bitter foods that as children they found repulsive? Why does folk law say “Good medicine always tastes bitter”?

After a lot of pondering I think I’ve got an answer but to make sense of it I need to lay out what I see as the relevant parts of the puzzle first.

Read time: 16 minutes (3100 words)

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The bitter truth is sweeter than we thought

Cocktail bitters like Angostura and Peychaud’s have pedigrees going back to the 1830’s. Looking like something out of a victorian apothecary these intriguing botanical preparations may indeed have medicinal properties deeper than anyone thought.

Following our recent infographic (Health Hack #1: An alternative to fizzy drinks) in which I recommended using Angostura bitters as a basis for a healthy fizzy drink, I felt I had more to say about bitters in general.

In traditional herbal medicine bitter herbs were considered aids to digestion through stimulation of bile and digestive juices. Taken fifteen minutes before a meal they were used to increase appetite –  the concept behind the idea of the aperitif – or after a meal as a digestive, but they are also thought to stimulate and ‘detoxify’ the liver, and generally are considered a ‘tonic’ to revivify the blood and to ‘enhance the vigour’ of the digestive system. Such vague and ill-defined terminology has led to these claims being largely dismissed. However, recent research is not only confirming the health value of bitter tasting substances but discovering that they have important physiological effects throughout the body.

The story of herbal bitters just took a fascinating turn that is proving to be sweeter than anyone might have imagined …

Read time: 12 minutes (2300 words) Continue reading

Even in the land of barbies and beer vegetarians DON’T live longer

A new study from Australia finds yet again that vegetarians don’t live longer than meat eaters.

We previously reported on a 2015 paper examining mortality among vegetarians in the UK based on data from the large Oxford EPIC study, which found no evidence for reduced mortality compared to the general meat eating population. [see our post UK vegetarians DON’T live longer than meat eaters study finds]

Now a similar analysis from the Australian 45 and Up Study has come to the same conclusions: there is no significant difference in all-cause mortality between vegetarians, semi vegetarians, pescatarians and regular meat eaters in Australia. Continue reading

Gary Taubes on American Heart Association confirmation bias

In our recent post ‘Amazing results challenge guidelines in new study‘, we looked at research that came to exactly the opposite conclusion to that of The American Heart Association who currently recommend replacing saturated fat with MUFAs and omega-6 PUFAs. The researchers concluded:

recommendations of supplementation with these fatty acids in the general diet should be revised.

The public at large are confused by what they see as flip-flopping over dietary issues: butter is bad one week, but ‘back’ the next. Many people find it hard to believe that such an authoritative body as the American Heart Association could be wrong. How can a few small researcher groups and flag-waving bloggers (like us!) possibly be right? Surely august bodies like the AHA sort through the data and discard the poor quality studies? Surely they can be trusted to do due diligence on our behalf?

These are reasonable thoughts for people to have and they are not wrong to think like this, but such convictions rely on our public agencies not slipping into the kinds of confirmation bias that science is supposed to protect us from.

In a recent Op-Ed Gary Taubes (science journalist and author of the best selling book Good Calories Bad Calories) tackles this topic head on. Continue reading

Low fat (but not full fat) dairy associated with increased risk of Parkinson’s disease

Read time: 4.5 minutes (850 words)

Intro

MedPage Today [full article here] drew my attention to a recent Harvard study published in the journal Neurology [abstract herewhich took a closer look at previously identified associations between dairy products and Parkinsons Disease. Their analyses were based on data from two large prospective cohort studies, the Nurses’ Health Study (n = 80,736) and the Health Professionals Follow-up Study (n = 48,610), with a total of 26 and 24 years of follow-up, respectively. An previous study (see below) found an increased risk of Parkinson’s with higher levels of dairy protein consumption.

The latest study looked more carefully at the different types of dairy product. They found that among those who ate 3 or more portions of low fat dairy per day (skimmed milk, low fat cheese and yogurt etc) 4 in 1000 went on to develop Parkinson’s disease, whereas among those who ate no portions of low fat dairy only 3 in 1000 developed the disease.

Comparing the two groups that equates to a roughly 33% increased relative risk. Of course that is only a rather piffling 0.1% absolute risk increase – hardly anything to worry about in the grand scheme of things. What makes this study interesting, however, is that the association did not exist for full fat dairy products only low fat ones.

Uric acid and Parkinson’s disease

The study’s authors speculate that the increased risk seen in the low fat milk group may be due to the ability of milk protein (casein and lactalbumin) to reduce uric acid levels. Parkinson’s disease and uric acid? I wasn’t aware of this link, so started digging into the research…

A particularly helpful review in Practical Neurology [Uric Acid’s Relationship with Stroke and Parkinson’s Disease: A Review] filled me in on the background.

It turns out that there is a growing body of evidence demonstrating an association between low uric acid levels and incidence of Parkinson’s disease. Not only do Parkinson’s sufferers tend to have have low levels of uric acid, but those with higher levels have slower and less aggressive progression of the disease. Importantly, some studies have identified that low uric acid levels four years prior to the onset of Parkinson’s symptoms has a stronger association than levels at onset of symptoms, suggesting that uric acid is linked to the  pathogenesis of Parkinson’s.

Uric acid BTW is an intriguing endogenous antioxidant which although primarily synthesised by the body is also influenced by diet. Excess levels can lead to the formation of crystals which is the basis of the painful condition gout, but can also contribute to kidney stones and kidney damage. Foods containing purines, such as shellfish, offal, meat and beer, can raise uric acid levels, as can alcohol and fructose, so should be avoided if you suffer from gout or kidney stones. The idea that such foods may be protective against Parkinson’s is interesting (although clearly one would not want to go as far as to cause gout!) On the other hand, dairy, cherries and vitamin C are associated with lower risk of gout and are classed as hypouricemic foods as they reduce uric acid levels.

It is believed that uric acid may exert a neuro-protective effect through it’s antioxidant action:

It has been hypothesized that uric acid reduces oxidative stress on neurons. This may have a significant bearing on therapeutic management of disease, as many neurological disorders are believed to result from oxidative stress. As a potentially modifiable risk factor, the prospect for uric acid and its derivatives to play a role in disease modification or prevention has great potential. – Pello et al, 2009

Studies looking at dietary associations with Parkinson’s disease have identified that uric acid lowering foods (e.g. dairy) are always associated with an increased risk of Parkinson’s, except for one. Vitamin C is the only uric acid lowering nutrient associated with reduced Parkinson’s risk: possibly because it is a powerful anti-oxidant itself.

Results from an earlier analysis of the Health Professionals Follow-up Study found clear trends indicating reduced incidence of Parkinson’s disease with increasing consumption of fructose and alcohol (uric acid raising foods) and an increased risk with higher levels of dairy protein consumption (a uric acid lowering food) Adapted from Xiang Gao et al, 2008

Full fat dairy

In the new study the increased risk for Parkinson’s disease was only associated with low fat dairy, not full fat. Why wasn’t full fat dairy associated with an increased risk of Parkinson’s?

For now there is no clear answer, but according to MedPage Today the authors of the study say “The lack of association with full-fat dairy products could be due to a countervailing effect of saturated fats. I think more research is needed to better understand the mechanisms involved in this association,”

The benefits of dairy fats have come up time and again, yet I still know many people who avoid full fat milk, cream, cheese and butter. See our posts:

Bottom Line

The size of the increased absolute risk of Parkinson’s disease associated with consuming low fat dairy products (0.1%) is too small to make it a reason in and of itself to avoid low fat dairy – unless of course, you have a family history of the disease in which case every bit of risk reduction helps.

For all of us, however, this study adds to the evidence of the benefits of full fat over low-fat dairy.

References

  • Intake of dairy foods and risk of Parkinson diseaseKatherine C. Hughes et al, Neurology, June 2017 [Abstract]
  • Low-Fat Dairy Linked to Small Increased Risk for PDKate Kneisel, Contributing Writer, MedPage Today, June 2017 [Full article]
  • Uric Acid’s Relationship with Stroke and Parkinson’s Disease: A Review Scott Pello et al, Practical neurology, Jul/Aug 2009 [Full article]
  • Diet, Urate, and Parkinson’s Disease Risk in Men, Xiang Gao et al, American journal of epidemiology, 2008 [PMC full text]

In the News

  • Why you’re better off eating FULL fat dairy: Consuming three or more portions of the low fat variety of yoghurt, milk or cheese raises the risk of Parkinson’s disease, Daily Mail [Online Article]
  • Low-fat milk linked to Parkinson’s risk, The Times [Online Article]