Slimming World’s view of low carb diets

  The UK Sun newspaper seems to have been the first to pick up this story: “'CARBFUSION' Low-carb diets are ‘damaging the nation’s health’ say Slimming World experts” (Ref 1). It was soon covered by other UK newspapers. Thankfully the nonsense seems to have been contained to this side of the pond. The Daily Mail ran with “Low-carb diets could make you FATTER, say Slimming World experts as they reveal the 13 ways carbs can help you LOSE weight” (Ref 2). The story emanated from a press release from Slimming World called “How low-carbohydrate diets are ‘damaging the nation’s health’” (Ref 3). I felt that the words “oh, for goodness sake” needed to follow such an ignorant statement. The press release was based on two surveys that had been commissioned by Slimming World. One done by YouGov on a sample of 2,103 adults (representative of the UK population) and one done by Slimming World on 2,481 of their members – both surveys were undertaken in November 2018. The UK wide survey found that 48% of people who have tried a low-carbohydrate diet found it difficult to follow (so 52% didn’t). The main reason for this was that they enjoyed eating carbohydrates too much (52%). Two thirds of respondents (66%) reported that they had heard that low-carbohydrate diets are better for weight loss. When it came to Slimming World members, 97% were pleased that they could enjoy carbs while following Slimming World’s plan. There was nothing terribly startling in any of these findings. The most interesting part of the media coverage was an article on the health and well-being web site “Healthista” (Ref 4). This article was based on an interview with Dr Jacquie Lavin, nutritionist and Head of Nutrition and Research at Slimming World. The article was called “13 ways carbs can help you lose weight” and it was repeated in the Daily Mail article. Let’s take a look at the 13 claims and see how accurate they are (direct extracts from the article are in black and my – ZH – comments are in red): “13 ways carbs can help you lose weight” “1) Carbs fill you up “At Slimming World, starchy carbohydrates such as pasta, rice, potatoes, cous cous, and quinoa are considered ‘Free Foods’, which you can eat freely to satisfy your appetite. “‘These foods are bulky and provide fibre which makes them filling and satisfying, especially when eaten with foods containing protein,’ says Lavin.”

ZH – Apparently supermodels eat cotton wool balls to fill themselves up. This would arguably be more effective than freely eating as many starchy carbohydrates as you like to try to feel full. The reason being, that those starchy carbohydrates are all packed with glucose, which will go straight into the blood stream and create havoc with blood glucose levels.

The goal of the successful slimmer should not be to feel full (having a full tummy is simply uncomfortable – there is no evidence that feeling full all the time will aid weight loss. In fact you’re probably eating too much if you feel full all the time). The goal of the successful slimmer should be to achieve stable blood glucose levels (the same goes for the person aiming to avoid type 2 diabetes). When blood glucose levels are normal and stable, any physiological driver to eat is substantially reduced. The best way to achieve and maintain stable blood glucose levels is to eat fat/protein foods (meat, fish, eggs and dairy) and not carb/protein foods (grains, fruits, legumes etc).

“2) Carbs keep you regular “Fact: Brits don’t get enough fibre and this can lead to sluggishness and constipation leaving us uncomfortable and bloated – not good for weight loss or our health.”

ZH – What goes in must come out. If you put more carbs in, then more carbs need to come out. That may be your idea of a good thing, but it’s not mine. Fibre seems to be the only waste product that is considered good. Waste in all other walks of life is, well, waste!

Brits allegedly don’t get enough fibre relative to a random fibre target made up by the government, working hand-in-hand with fibre providers a.k.a. cereal companies. Constipation should be defined as discomfort in passing stools, not as not doing a number two several times a day. If you’re not producing much waste and you feel comfortable getting rid of the waste that you do have, you’re eating efficiently.

“3) Carbs are full of nutrients “‘If you are really restricting or have completely cut out carbs you are at risk of missing out on a lot of important vitamins, minerals and especially fibre,’ says Lavin.”

ZH – do you see how fibre has been used as a rationale for the first three points already? The most important thing to say about carbohydrate is that we don’t need to consume it. But then an article raving about carbohydrate is not going to include that vital fact. I constantly see fibre being used as the rationalisation for why we should eat carbs, but carbs are not essential and so fibre is not essential – that is an inescapable fact combined with inescapable logic.

Because carbohydrates are not essential for human to consume, it cannot be the case that we need to consume carbohydrates for any micronutrients (vitamins and minerals). Carbohydrates can provide vitamins and minerals, but you will always be able to find a fat/protein (usually animal) food that provides more.

I present the evidence for this point in the table below. The table includes calories, essential fats, protein quality (note that only the animal products score over 100), vitamins and minerals. The values are all presented for 100g of product. The ‘winner’ in each row is highlighted (in bold), so rice wins on calories (not sure that’s one you want to win). Oily fish wins on essential fats (and in an ideal omega-6/omega-3 ratio). Liver wins for most vitamins. Cocoa powder wins for most minerals (you’d be better off enjoying very high cocoa content dark chocolate than starchy carbs). Where pasta or rice did do well, I’ve added a note to show that a fat/protein food would still beat the starchy carb hands down.

(All per 100g of product) (Refs 5-10 for food items)	Chicken Liver	Sardines	Eggs	Whole wheat pasta	Brown rice	Cocoa powder
Calories	116	208	143	348	370	228
Omega 3 (mg)	6	1,480	74	27	44	0
Omega 6 (mg)	486	3,544	1,148	529	1,000	440
Protein Quality (100+ = complete protein)	149	148	136	43	75	90
Vitamins (RDA)
A Retinol (900 mcg)	3,290	32	139	0	0	0
B1 (1.2 mg) Note 1	0.3	0.1	0.1	0.5	0.4	0.1
B2 (1.3 mg)	1.8	0.2	0.5	0.1	0.1	0.2
B3 (16 mg)	9.7	5.2	0.1	5.1	5.1	2.2
B5 (5 mg)	6.2	0.6	1.4	1	1.5	0.3
B6 (1.7 mg)	0.9	0.2	0.1	0.2	0.5	0.1
Folate (400 mcg)	588	12	47	57	20	32
B12 (2.4 mcg)	16.6	8.9	1.3	0	0	0
C (90 mg) Note 2	17.9	0	0	0	0	0
D (15mcg)	neg	6.8	0.9	0	0	0
E (15 mg) Note 3	0.7	2	1	0	1.2	0.1
K (120 mcg)	0	2.6	0.3	0	1.9	2.5
Minerals (M)
Calcium (1,000 mg)	8	382	53	40	23	128
Magnesium (420 mg)	19	39	12	143	143	499
Phosphorus (700 mg)	297	490	191	258	333	734
Minerals (T)
Copper (0.9 mg)	0.5	0.2	0.1	0.5	0.3	3.8
Iron (18 mg)	9.0	2.9	1.8	3.6	1.5	13.9
Manganese (2.3 mg)	0.3	0.1	0.0	3.1	3.7	3.8
Selenium (55 mcg) Note 4	54.6	52.7	31.7	73	23.4	14.3
Zinc (11 mg)	2.7	1.3	1.1	2.4	2	6.8