Comments on: Carbohydrate and triglycerides: do low-carb advocates have a point?

By: Bill Shrapnel

Bill Shrapnel — Sat, 21 Feb 2015 01:46:58 +0000

Hello Elmarie. When it comes to the question of whether the evidence available in ~1980 justified the introduction of a dietary guideline on fat, my answer is yes and no.
The randomised controlled trial evidence, which the latest meta-analysis addresses, was mixed. Other meta-analyses have different findings, so I guess we can still say the evidence is mixed.
But when those first dietary guidelines were put together the scientists didn’t just look at RCTs. They also looked at data from animal studies, epidemiological evidence, and mechanistic studies – especially the effects of different types of fat on blood cholesterol. In the end, it was decided that the evidence supported the replacement of saturated fat with polyunsaturated fat. But how would this be communicated to the general public?
THIS was where the big mistake was made. It was assumed that the average person wouldn’t be able to understand ‘replace saturated fat with polyunsaturated fat’ or even ‘lower saturated fat’. So, it was decided that the simple message would be ‘eat less fat’. If people followed it, saturated fat intake would go down as total fat intake went down (and carbohydrate intake went up).
People weren’t concerned that there might be a negative side effect to ‘eat less fat’. In fact, it was thought that ‘eat less fat’ might lower the risk for breast cancer, bowel cancer and overweight.
Thirty years later we worked out that the original message – replace saturated fat with polyunsaturated fat – was actually the correct one and that ‘eat less fat’ (which encouraged people to replace all type of fat with carbohydrate) achieved nothing.
‘Replace saturated fat with polyunsaturated fat’ is what we should be implementing now but lots of people are muddying the waters for one reason or another. Regards, Bill

By: Elmarie

Elmarie — Tue, 17 Feb 2015 13:27:34 +0000

Bill, I would appreciate your response to this recent meta- analysis (link below)
Evidence from randomised controlled trials did not support the introduction of dietary fat guidelines in 1977 and 1983: a systematic review and meta-analysi
http://openheart.bmj.com/content/2/1/e000196.full

thank you

By: Jen

Jen — Sat, 24 Jan 2015 21:43:55 +0000

The fatty acid content of breastmilk varies according to the mother’s diet. If she is in energy balance up to 85% of fatty acids will come from her diet. There will certainly be some saturated fat as a result of synthesis in the breast tissue and mobilisation of fat stores if required but breastmilk doesn’t contain just saturated fat and depending on the mother’s diet saturated fat won’t be the dominant fatty acid.

By: Bill Shrapnel

Bill Shrapnel — Thu, 22 Jan 2015 02:32:07 +0000

Hi Derick
I totally agree with you that a healthy diet should be both enjoyable and sustainable. Extreme or purist approaches usually fail on both counts.
Regarding ‘poor carbohydrates’, the definition is still not universally agreed. But if we define it as nutrient-poor carbohydrate-rich foods that have a high GI and/or lacking in fibre we are looking at foods like white rice, baked goods (biscuits, cakes, pastries), confectionery and many sugar-sweetened beverages. Many of these are treat foods which contribute to enjoyment but don’t do much for nutrition.
So, for a young, healthy person such as yourself, the answer is ‘moderation’.
Personally, I don’t quantify how much of these foods I eat. Rather, I respond to the circumstances, so intake varies from day to day. Maybe I should write a book ‘The Commonsense Diet’.
Regards, Bill

By: Derick

Derick — Thu, 22 Jan 2015 01:19:07 +0000

Bill,

I am a 28 year old male with very normal blood pressure, blood sugar and blood lipid levels. I limit my calories and alcohol and I do a mix of cardio and strength exercise.

Since I don’t seem to be at risk for chronic illness like heart disease or diabetes, how can a guy like me incorporate so-called “poor carbohydrates” into a healthy diet? I am a big believer that any diet should be enjoyable to the individual to be sustainable over the long term. I eat jasmine rice and pasta and potatoes and bread and coconut milk because I enjoy them and I can factor other very nutritious foods around them.

What is some sound, workable and simplistic advice I can follow to enjoy eating these foods without stressing myself out too much in the process?

By: Bill Shrapnel

Bill Shrapnel — Thu, 15 Jan 2015 04:06:51 +0000

Hi Ross.
Science teaches us to be sceptical.
You say we have had very poor nutrition science over the last 50 years or so – a comment frequently heard. However, I think it needs a little context. Once nutrition science worked out all the requirements for essential nutrients a new phase of nutrition science began. This focussed on the role of nutrition in reducing the risk for chronic diseases, such as cardiovascular disease, cancer, diabetes and obesity. The first Dietary Guidelines for Australians were published about 35 years ago and summarised the nutrition science available at the time. By today’s standards you could say this science was relatively poor, but it was the best available at the time. It was a whole new field.
ONE of the recommendations was to ‘eat less fat’- good catch-all advice that it was thought would lower the risk for several chronic diseases. But then nutrition scientists undertook some very large, very good studies to test the hypothesis.
Very unfortunately, despite the quality of the science, many nutritionists refused to believe the results: ‘Eat less fat’ was NOT evidence-based advice – it did nothing. We knew this in 2006. Health authorities should have adjusted their advice much earlier but the wheels turned very slowly and the conservatism ran deep. We are paying the price for it now. Nutrition authorities are being beaten over the head by lay ‘experts’ purporting to have discovered that low fat diets don’t work. They didn’t do the research!
Nutrition science now needs to reassert itself and reclaim its authority. Regards, Bill

By: Vigna

Vigna — Mon, 05 Jan 2015 05:58:21 +0000

Vitamine D ???? We can of course make it ourself with only 20 min exposure to sun.

By: PhilT

PhilT — Tue, 23 Dec 2014 10:55:23 +0000

Low carb proponents are generally of the opinion that a) saturated fat is not a bad thing per se, b) increased dietary saturated fat does not correlate with increased saturated fat in the blood stream and c) if you take out carbohydrates you need a replacement energy source and given a) and b) why not use saturated fat if you wish to avoid inflammatory seed oils.

There is also evidence that in low carbohydrate diets the saturated fat is preferentially oxidised as fuel so it generally isn’t seen as an issue. Reams of weak epidemiology about sat fat in the context of a high carbohydrate intake isn’t going to sway anyone on this I suspect.

By: Lauren

Lauren — Tue, 23 Dec 2014 07:39:00 +0000

Coconut oil is about 80% saturated fat

By: George Henderson

George Henderson — Tue, 23 Dec 2014 05:41:25 +0000

Everyone is in agreement NOW to avoid trans fats, but the reason everyone ate trans fats in the first place is that they were told saturated fat was bad for them!
Also, there is no such food as a pure saturated fat. Butter fat is about 40% MUFA. If you eat more fat, you eat more PUFA, even without seeking out seed oils.