Tuesday, April 12, 2011

Lindeberg In a Nutshell

I felt like kind of an idiot posting about Lindeberg yesterday without knowing much about him. So I got ahold of Food and Western Disease (FAWD) and did a little skimming (which, incidentally, goes for the low, low price of 75 bucks on Amazon). I will probably read the whole thing despite my waning interest in the technical side of nutrition. The book is pretty simple and straightforward reading as far as I can tell, despite the fact that it seems to be more of a textbook, and it is chock full of references.

So for anyone who wants a cliff notes version of Lindeberg and FAWD I'll attempt one here.

FAWD is an updated, revised and English version of a medical tome Lindeberg wrote in 2003 in Swedish, it was published last year so represents his most current views, I assume. FAWD has a forward by Loren Cordain, who also seems to be something of a lapsed lipophobe.

Lindeberg led the famous (some would say infamous) Kitava study. He doesn't have a Wikipedia page so I don't know much about him beyond the fact that he's currently associate professor at Lund University in Sweden (which is some country where everyone has to have blond hair and drive Volvos at very slow speeds, trust me, I've been there).

As he writes in the preface:
Now I was hooked for real. I began to read scientific papers systematically. After a while, I cut grains, dairy, salt and processed food from my own diet, and my blood pressure, weight and blood lipids went from normal to low. I could see no obvious risk with a diet mainly based on meat, fish, root vegetables, vegetables, eggs, fruits and nuts. I informed my patients who were usually interested and often surprised of the results.

I phoned Goran Burenhult, an archaeologist who had also read Eaton's paper and who had visited the traditional horticulturalists of the Trobriand Islands, Papua New Guinea. He convinced me to organise a clinical study there, due to the signif­icant proportion of elderly and their ancestral dietary pattern. This is the Kitava study, mentioned here and there in the text.

Lindeberg on salt

My opinion on salt is that it totally rocks and not simply because it actually is a rock. I'm a big fan of Gary Taubes essay (which no longer seems to be freely available) on the bad science behind NaCl research, but that's probably because I like to eat tons of salt. I'd probably even eat tofu if it was rolled in salt and fried in lard. I do think it's important to eat real salt.

Lindeberg takes the traditional view on salt that we don't need and probably shouldn't ingest very much of it.
Quitting smoking, daily walks, extra vegetables and fruits, Mediterranean-like food choices, as well as reducing our consumption of energy-dense foods and salt are one step on the path, but it is evidently not enough. [FAWD, preface]
Mediterranean-like food choices? Extra fruit and vegetables? Hmmmm . . .
A starting point for discussions about salt and health was a French experiment 100 years ago showing raised blood pressure after high salt intake. Considerable evidence now suggests that restriction of dietary sodium below 100 mmol Na/day (<6 g sodium chloride or <2.4 g sodium per day) will reduce blood pressure and prevent cardiovascular disease in people with hypertension. Since only a minority of middle-aged and elderly Westerners have optimal blood pressure (< 120/80 mm Hg), and since low levels are more healthy than average or high levels, most people would seem to benefit from a low salt intake. Several studies suggest that dietary salt is a contributing factor in the development of stroke and heart failure, particularly among overweight people, and possibly independently of blood pressure. A correlation between sodium intake and stroke has also been noted among Europeans, as well as in China and Japan. The influence of dietary salt on ischaemic heart disease is more controversial, but here, again, the risks with high salt intake may be highest for overweight subjects. [FAWD, pp 26-27]
Consumption of salt (sodium chloride, NaCl) was most likely low during human evolution, similar to what was the case during the evolutionary history of land animals. An average Westerner consumes 150-200 mmol/day (9-12 g salt/day), which can be compared with an estimated intake of less than 30 mmol/day among prehistoric hunter-gatherers and 1 mmol/day among the Yanomamo Indians in the Amazon rainforest. Note that not just sodium, but also the chloride intake, was originally very low. In modern times, the balance between both sodium and potassium, as well as between chloride and bicarbonate, has shifted strongly in favour of sodium and chloride.

The physiological need for sodium has been estimated to be less than 0.6 mmol/kg of body weight/day. Since the intake among the Yanomamo Indians fell below this level, the actual requirement is probably considerably lower. Real sodium deficiency in the tropics occurs because of rapid salt depletion among people who are used to a high salt intake. Salt supplements are therefore only required in the initial 10-15 days, until the sweat glands reset their salt secretion patterns. [FAWD, pp 37-38]
I have to admit he's got a point, and the part about salt glands resetting is quite interesting.

Unlike the idiotic notion that we overeat because we are genetically programmed to do so in times of abundance, I can see a reasonable case to be made for humans being over-programmed for a scarce resource like salt that is now screwing us up.

Speaking of salt, I highly recommend Salt: a World History.

Lindeberg on saturated fat

Lindeberg is pretty skeptical of SFAs.
However, studies in animals have shown high-fat diets to be a partial cause of both atherosclerosis and insulin resistance. In some of these studies, a very moderate increase in dietary fat has caused abdominal obesity and insulin resistance, one of the main culprits in Western disease. Moreover, this effect has been independent of total caloric intake. In other animal experiments, a high-fat diet has led to intracellular fat accumulation, which is suspected of leading to long- term loss of cell function by way of lipotoxicity. This disturbance is closely related to insulin resistance and the metabolic syndrome. [FAWD, pp 23]
Do these animal studies involve rabbits and mice? Because last I checked these creatures weren't exactly apex predators.
Ancestral human diets are expected to have varied substantially with regard to saturated fat, depending on habitat. For populations with 40-50% dependence on meat and/or fish, saturated fat is estimated to have been 5-15% [here Lindeberg cites Cordain's 2006 paper]. In addition to the low total fat content in wild game, there is less saturated fat as proportion of total fat, in comparison with modern domesticated farm animals. Saturated fatty acids constitute more than 50% of the fat storage depots of wild mammals, whereas the dominant fatty acids in muscle and all other organ tissues, includ­ing bone marrow, are polyunsaturated and monounsaturated fatty acids. Since subcutaneous and abdominal body fat stores are depleted during most of the year in wild animals, polyunsaturated and monounsaturated fatty acids constitute the majority of the total carcass fat. The intake of saturated fat among shore-based populations was particularly low, with a high percentage of marine fat from fish and shellfish.

The percentage of saturated fat is low in most nuts. Coconut fat, however, is dominated by saturated fat. The dominant saturated fatty acids in coconut fat are lauric acid (12:0) and myristic acid (14:0), while the amount of palmitic acid (16:0), which is the main saturated fatty acid in meat and dairy products, is low. The presence of coconuts in prehistoric Africa is very uncertain [here he cites this paper]

The majority of saturated fat in today's Northern European diets comes from dairy products, edible fats and delicatessen products. [FAWD, pp 45] (emphasis mine)
Now we get to the meat of the argument (Ed., stop with the lousy puns). I'm not really familiar with Cordain, but I believe he makes the same lipophobic (or I should say, SFAphobic) argument. Wild animals are much leaner than modern grain-fed animals (no argument there), and the fats they do have are mostly not saturated. Well, I'm not really qualified to dispute this, but this is a lot of supposition in my opinion. These pictures of free-roaming bison show quite a lot of subcutaneous and especially abdominal body fat. Also, I believe Cordain has revised up his estimates since his 2006 paper.

Since the point of this post is to briefly summarize Lindeberg's views, I'll leave it at that.

(*cough*  bullshit!  *cough*)

Lindeberg on fruits

He's a pretty big known as a pretty big fan.
For people on a Western diet, fruits and vegetables may provide an important source of essential vitamins, minerals and trace elements. However, once nutri­ent requirements are met it is uncertain whether these foods are important for long-term health in the prevention of Western disease. The high water content of fruits and vegetables is expected to prevent obesity by way of satiation. Several studies found beneficial effects on health-related variables of lifestyle or dietary advice, which included increased amounts of fruits and vegetables. In the successful Lyon Diet Heart Trial, fruits and vegetables were some of the foods recommended to the intervention group, which conceivably explained some of the reduced mortality in that group. Epidemiological prospective studies suggest a slightly reduced risk of cardiovascular disease and several types of cancer. [FAWD, pp 24] (emphasis mine)
I love the passive voice, and by that I mean I hate it.

Mistakes were made, innocent civilians were, uhm, made non-functional.

The high water content of fruits and veggies was expected to prevent obesity.

I know, a cheap shot, the passive voice can't really be avoided in a textbook tome such as this. Still, it always reminds me of some sleazy politician or bureaucrat dodging blame and accountability. Here Lindeberg seems to be leaning toward fruits and veggies.

But the next paragraph is:
However, no randomised controlled trial has specifically addressed the indepen­dent effects of fruits and/or vegetables on the incidence of death or serious disease such as cardiovascular disease or cancer. In a study on males with angina pectoris, Burr and co-workers found no effect on total mortality or cardiovascular disease of advice to eat 4-5 portions of fruit and vegetables and drink at least one glass of natural orange juice daily, and also increase the intake of oats. Hence, there is as yet no strong evidence that a low intake of fruits or vegetables is an independent cause of Western disease. [FAWD, pp 24] (emphasis mine)
Now there's a sentence I can totally get behind.

Interestingly, that's about it as far as fruits being mentioned. I've heard Lindeberg is big on fruit, but I find little evidence of it in FAWD.

OK this has gone on way too long, but that's my quick and dirty take on Lindeberg and FAWB.

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