Funkar eller inte.

Nils Funcke vill belägga departementens tjänstemän med munkavel gentemot sina departementschefer (!?).

Då undrar jag; Hur tänkte han då?

Nils Funcke tycker inte om att näringsdepartementet med anledning av Aftonbladets granskning själva granskade sina notor.

Men, hur tänkte han då?

Det är väl ett utmärkt tillfälle att granska bokföringen, när det ändå kommer skrivas om det i tidningen. Om inte annat för att kunna svara på vad tidningen skriver. Eller tycker Funcke att det är bättre att departementet med ministern i täten ska stå utan svar när anklagelserna börjar hagla.

Svarslösa inför frågan "Har ni tittat på det här?"

Det tycker Funcke är bättre än att departementet har gått igenom och själva granskat sina notor, rättat det som är fel och framförallt blivit varse att det begåtts fel. Det är väl det som kallas självgranskning, men det tycker alltså Funcke är en dålig ide´ och strider mot grundlagen (!?).

Funcke tycker alltså det är bättre att departementen inte håller efter sin egen bokföring (!?), låter fel bestå så de inte kan tolkas som att man "städar upp" (!?).

Ja, hur tänkte han då?

Så om media ska granska den politiska makten, men den politiska makten inte får rätta fel, i alla fall inte innan Aftonbladet har fått skriva om det, vad är då meningen med det?

Det är det märkligaste jag läst på väldigt länge.

How Does Eating Avocados Affect Cholesterol?

Avocados contain plenty of MUFAs, most of which is oleic acid. (Photo by Muffet)

Everyone knows avocados are high in fat, but does that make them healthy or unhealthy? In this post, we'll look at how avocados affect cholesterol levels.

Avocados are technically large berries of the avocado tree, each berry containing a single seed usually called the avocado stone. There are several different cultivars, but on average avocados contain about 15 grams of fat, 9 grams of carbohydrates and 2 grams of protein per 100 grams. Most of the fat (~10 grams) is monounsaturated, while the rest is roughly half saturated and half polyunsaturated.

Most health enthusiasts are either pro-saturated fatty acids (SAs) or pro-polyunsatured fatty acids (PUFAs) – and if you're a long-time reader of this blog, you already know which category I lean towards. Monounsatured fatty acids (MUFAs), however, seem to represent something of a "neutral" group of fats to many. Olive oil, for example, is high in MUFAs, and almost all studies find it either beneficial or at least neutral: generally, LDL decreases and HDL either increases or stays the same.

So if olive oil is good for you, what about avocados? Since both are high in MUFAs, specifically oleic acid, one might expect to see similar results. In rats, adding avocados to their diet seems to increase HDL and decrease triglycerides (link). Avocado leaf extracts appear to be especially effective (link).

Avocados, cholesterol & healthy subjects

Experiments on humans, unfortunately, are not always as unequivocal. The earliest human study I could find compared an avocado-enriched diet with a diet high in complex carbohydrates and low in fat – namely, the lipid-lowering diet advocated by the American Heart Association (link). The study included 15 women who were randomly assigned to one of the diets for three weeks, followed by 3 weeks on the other diet. Only the avocado diet, on which the women ate between half and one and a half avocados per day, resulted in a statistically significant decrease (~8%) in total cholesterol levels. This was due to a lowering of LDL without affecting HDL, whereas the complex carbohydrate diet lowered HDL levels by ~14%. So much for the heart-healthy effects of low-fat diets.

The second study included 16 healthy volunteers who were fed three different diets for 2 weeks: a high-MUFA diet consisting of 30% fat (75% of which came from avocados), a free diet including avocados, and a low-saturated fat without avocados (link). Both the high-MUFA diet and the low-SA diet reduced total cholesterol and LDL. However, the low-SA diet also also reduced HDL and increased triglycerides, while the other two diets reduced triglycerides. Again, the low-fat diet with an emphasis on limiting saturated fats was the most harmful for cholesterol levels.

I find it somewhat surprising that the free diet with avocados apparently also reduced HDL, even though the authors say the volunteers ate the same amount of avocados as during the high-MUFA diet. Unfortunately I don't have access to the full paper, so I'm not sure what the free diets were like in reality. Perhaps the volunteers simply ate more during the free diet, which could have skewed the results, or maybe the SA/PUFA ratio was significantly lower on the free diet for some reason.

Avocados and people with high cholesterol

Another study included 13 patients with high LDL cholesterol (link). The patients were given a standard vegetarian diet, a vegetarian diet enriched with avocado or a free diet that included avocados. The standard vegetarian diet consisted of 70% carbs, 20% fat and 10% protein, while the vegetarian avocado diet was 60% carbs, 30% fat and 10% protein. The vegetarian avocado diet reduced LDL, whereas the free diet increased it slightly. Only the standard vegetarian diet significantly reduced triglycerides – however, it also reduced HDL more than the other two.

The results of this study seem to contradict the two earlier studies, since simply adding avocados to the diet resulted in slightly lower HDL and slightly higher LDL – in other words, their cholesterol levels worsened. Genetics may play a role here, as some individuals who are predisposed to higher LDL levels seem to react negatively to foods that generally improve the cholesterol ratio. The authors themselves state:

"Low-fat, carbohydrate-rich vegetarian diets may be harmful to hypercholesterolemic patients. The avocado addition to a vegetarian diet does not correct these undesirable effects. To obtain beneficial effects on lipid profile with avocado, lower amounts of carbohydrates and polyunsaturated fatty acids are probably needed."

Yet another study compared the effect of an avocado-enriched diet on healthy subjects and patients with slightly elevated cholesterol levels (link). In healthy participants, total cholesterol decreased by 16% on the avocado diet. In participants with high cholesterol, total cholesterol decreased similarly, with LDL and triglycerides decreasing by 22% and HDL increasing by 11%. The authors conclude that a high-MUFA diet containing avocados improves lipid profile in healthy and especially in mildly hypercholesterolemic people.

Conclusion

Compared to low-fat diets, diets containing moderate to high amounts of monounsaturated fatty acids from avocados seem to result in better cholesterol levels. In healthy people, replacing carbohydrates with avocados generally lowers LDL without affecting HDL, similar to olive oil. In people with high cholesterol, replacing carbohydrates with avocados appears to reduce LDL and, in some cases, increase HDL.

The controversial result is the lower HDL in free diets with avocados. Does simply adding an avocado to your diet actually make cholesterol levels worse? This is a tricky question, since adding an avocado would mean an increase in total energy intake, unless it also means you eat less of something else – which would be the case, unless avocados somehow increase appetite. One possibility is that when the participants added avocados (and thus MUFAs) to their diet, they reduced their consumption of other fatty acids while keeping total energy intake the same. Reducing saturated fatty acid intake could result in lower HDL, although this doesn't necessarily explain the higher LDL. Without knowing what the participants actually ate during their free diet periods, it's difficult to say what the cause is.

While it's generally taken for granted that a) olive oil reduces LDL and has a neutral or positive effect on HDL and b) this effect is due to the high MUFA content of olive oil, there are differences in the food sources of MUFAs. Both avocados and olive oil are high in oleic acid, but olive oil contains squalene, whereas avocados do not. Squalene is a precursor in cholesterol synthesis and is metabolized to cholesterol in the body. Avocados, on the other hand, contain beta-sitosterol, which lowers LDL.

Finally, genes play a major role in cholesterol levels. Apolipoprotein E genotype affects how individuals react to dietary fatty acids and also cholesterol-lowering drugs like statins. Without knowing the genotypes of the participants in the studies, it's hard to say how generalizable the results are.

For more information on diet and cholesterol, see these posts:

Want to Increase Your HDL Cholesterol by 50%? Sage Tea May Be the Answer
High HDL Cholesterol Reduces Risk of Dying in Men
Hibiscus Tea Increases HDL, Lowers LDL and Triglycerides
The Twinkie Diet: Thoughts on Weight Loss and Cholesterol

Vacation...all I ever wanted...

I saw this little tidbit about vacations last week on Sunday Morning:



Apparently a vacation ain't great because you're doing it, but because you're anticipating doing it.

Well, this week is my week for a vacation with the kids. I can tell they had fun thinking anticipating it. They can give a day-by-day rundown of activities: the few days of "staycation" -- fun things here in the Columbia area (the zoo, a Blowfish baseball game, the water park, and maybe even a return to Carowinds) -- and a few days away at a cabin with a day trip to Folly Beach. I think this "vacation anticipation effect" for me was more a matter of helping me focus to get a few crucial tasks done beforehand.

So, even though the anticipation of a vacation apparently brings more joy than the actual vacation, I'll still try to enjoy the week. ;-)

Maybe those social scientists from the 1980s knew what they were talking about...

Footnote

How do you dramatize the life of a professor? And why would you want to? Don’t they just write, teach, and grade papers? How do you make that interesting? Most films that deal with academic life focus primarily on students, and with good reason: they tend to lead more interesting lives. They party, they do sports, they get in trouble, they have crazy relationships and friendships. Animal House is perhaps the most famous embodiment of the college movie.

But professors? What could be interesting about their lives? Wonder Boys is a wonderful exception to the expectation that a movie about professors would be boring (and it lives up to the great book it is based on). Certain scenes in other movies pop out, one of my favorites being Dustin Hoffman’s role as a coffee-obsessed professor in Stranger Than Fiction. The Coen Brothers produced an odd, but beautiful, film about a Jewish professor in their retelling of the story of Job in A Serious Man. The Visitor is an equally sedate, but moving, story of a professor finding his way in the world. There are other examples, but you get the idea.

With a title like “Footnote” it might sound like an academic treatise, not a film rife with conflict and dramatic tension. The film takes place at Hebrew University in Jerusalem. There are two protagonists, both professors, both by the name Shkolnik. A mistake is made by the Ministry of Education when they notify the wrong Professor Shkolnik about winning the Israel Prize for Talmudic Studies. This mistakes reveals a host of problems and family dynamics. 

The film causes you to consider one set of ethical questions after another. What is the right decision when faced with a true dilemma (where there is no perfect solution)? Given its setting--not just that it is about Biblical scholars, but is set in Israel--one can see the biblical overtones. Is this movie about the fifth commandment, that one should honor his mother and father? Is a twist on the story of Jacob and Esau? 

There are lots of other themes to consider. What are the duties of a father to his son and a son to his father? What are our ethical duties to our rivals? Are any secrets worth keeping? The movie is about the very language we use day in and day out. What does this language mean? How do we use it? What is the role of memory? And how does language--and the way we archive our stories--affect our memories?

There are subtle critiques of academic life. Why do we do research? Teach? What value do these activities add to society? To the lives of the academics? In some of the films more humorous moments, it pokes fun at academics (and we certainly know that academics are highly pokeable). 


You may have noticed that I haven’t revealed much of the plot. True. That’s because I want you to come see it with me and then discuss it at a coffee shop afterwards. One of my favorite things to do is to watch a film like this and then debate everything about it--meanings, techniques, characters. How often is a movie like this--about professors that takes place in an international setting and is replete with ethical quandaries to chew on--playing across the street from your office, especially for a guy like me who loves this kind of film?

Antioxidants and Intermittent Fasting – Good For Longevity?

Are blueberry antioxidants beneficial for intermittent fasting? (Photo by Simply Bike)

Is it possible to live longer by combining the benefits of intermittent fasting (IF) and plant polyphenols? A new paper claims that taking polyphenol antioxidants during dietary restriction increases the lifespan of mice more than dietary restriction alone. The antioxidants used in the study were blueberry, pomegranate and green tea extracts.

The subject of the paper – "Potentiation of dietary restriction-induced lifespan extension by polyphenols" – is certainly enough grab the attention of anyone interested in life extension. The abstract seems promising too (link). Here's a quote:

Dietary restriction (DR) extends lifespan across multiple species including mouse. Antioxidant plant extracts rich in polyphenols have also been shown to increase lifespan. We hypothesized that polyphenols might potentiate DR-induced lifespan extension. [––] Polyphenol compounds may potentiate IF-induced longevity by minimizing specific components of IF-induced cell stress.

Let's look at these claims in more detail. First off, it's not clear from the abstract what exactly the authors mean by "dietary restriction". The full paper, however, reveals that they use the term to describe pretty much any kind of diet where access to food is limited, including traditional calorie restriction and intermittent fasting.

The longevity confusion

The problem with that opening sentence is that dietary restriction extends lifespan across multiple species only when it equals calorie restriction. That is, you can make a mouse live longer by only feeding every other day, as long as it results in less calories consumed. This is an important distinction, because many people – including longevity scientists – keep propagating the myth that intermittent fasting has the same benefits as calorie restriction. It doesn't. The reason that IF prolongs lifespan in some species is because the animals fail to compensate for the missed calories on their feeding days.

The next sentence is just as problematic. Yes, plant antioxidants have been shown to increase lifespan, but the question is, compared to what? So far, no one has succeeded in exceeding the known maximum lifespan of mice by feeding them antioxidants. Instead, what we see in many studies is that the antioxidant group lives longer than the control group.

The problem is that almost always, neither group lives very long. Poor diets, poor animal husbandry, poor environment – all play a role in how long the animals live. So, in essence, the antioxidants merely make the unhealthy mice a bit healthier. But this is like making a human live 70 years instead of 60 years by giving them some veggies with his daily bread and then claiming that "vegetables extend human lifespan".

Comparing lifespans

That said, there are some interesting figures in the full paper. The graph below shows the survival rates of the three groups; one fed the control diet, the second fed the same diet but only every other day, and the third fed a diet supplemented with polyphenols every other day:

There's a big drop in the survival rate of the control group around 22 months. For the IF groups, the survival curves look a lot better. So how does this compare to the average lifespan of similar mice kept in good laboratory conditions? Here's a graph of age ranges and survivorship of C57BL7/6J mice (the same strain used in this study):

This survival curve is based on a cohort of 150 male and 150 female mice. As you can see, at 28 months half of the mice are still alive. That's about 850 days, which is a pretty normal figure for mean lifespan of this strain of mice in the literature.

Once again, in the antioxidant study the control group dies earlier than is normal. For some reason, half of the mice are dead at 22 months instead of 28 months. One possible reason is the use of a high-fat diet to "mimic the effects of a Western diet", as the authors put it. This seems like a strange idea to me, because a typical Western diet is no more a high-fat diet than it is a high-carbohydrate diet. Furthermore, plenty of humans (myself included) seem to do quite well on a high-fat diet, whereas with mice it's somewhat different.

The survival curve of the IF mice in the first graph is slightly better than that of the normal-fed mice in the second graph. But that is hardly a surprise, given that both the IF group and the IF + antioxidant group had lower body weights than the control group. In other words, the intermittent fasting once again made the mice eat less than the control group, which in turn resulted in a slightly longer lifespan. It's good to keep in mind, however, that with just 10% calorie restriction longer lifespans have been reported in other studies, so the result is not too impressive.

Conclusion

Perhaps the most interesting result is that the IF + antioxidant group lived slightly longer than the IF group. There's no concensus as to whether it's a good idea to combine CR or IF with antioxidants. It may be that plant polyphenols are essential for optimal nutrition and good for activating sirtuins (which play at least some role in longevity), but there is also some evidence suggests that taking antioxidants may interfere with hormesis and thus diminish the effects of CR.

In this study, the antioxidants had a beneficial effect. While the IF diet by itself activated pro-inflammatory pathways, adding plant polyphenols to the diet blocked this effect. The authors identified 20 gene sets that were down-regulated by the addition of polyphenols, most of them related to immune response, inflammation, cell differentation and tumorigenesis. 

This suggests that if you're doing intermittent fasting, adding some blueberries, pomegranates and green tea to your diet may not be such a bad idea. Note, however, than the mice did not have access to polyphenols during their fasting days, so this study tells us nothing about taking antioxidants during fasting. It also doesn't say much about how polyphenols affect regular calorie restriction without IF in humans.

For more information on intermittent fasting and longevity, see these posts:

Lithium in Drinking Water May Lead to Longer Life
Does Intermittent Fasting Increase Lifespan?
Alternate-Day Feeding and Weight Loss: Is It the Calories Or the Fasting?
Slowing Down Aging with Intermittent Protein Restriction