The National Obesity Forum has today published a report saying we should be eating more fat and less carbohydrate in order to lose weight. The debate around fat has been gathering pace over the past few years and we are expecting a draft report from the Scientific Advisory Committee on Nutrition (SACN) on the subject of dietary fat and healthy soon. So should we eat more fat and less carbohydrate and has the advice for healthy eating changed?
The best way to lose weight is to follow a diet that triggers weight loss for you as an individual, that you can stick with for long enough to meet your goals. Some of my clients do chose a low carbohydrate diet as the best approach for them (many others do not) but it’s not the best choice longterm. So let’s take a look at why.
Firstly we know that fibre is important for our health. We need 30g/day and we should have both insoluble and soluble fibre. Insoluble fibre comes from wholegrain foods, vegetables, potato skins, nuts and seeds. This type of fibre helps waste pass more quickly through the gut, which keeps our bowels healthy and reduces our risk of bowel disease. Studies have shown that wholegrain cereals in particular reduce our risk of heart disease and stroke. So good helpings of unsweetened wholegrain breakfast cereals, brown rice, wholemeal cous cous and wholemeal pasta are a great option. Soluble fibre comes from oats, rye and barley, fruits, root vegetables like carrots and potatoes, beans and pulses like kidney beans, chick peas and baked beans. This type of fibre helps keep our stools soft and makes them easier to pass, reducing our risk of bowel disease. Studies have shown that oats in particular help reduce blood pressure. I know from my practice that people struggle to reach the 30g/day target and those on a low carbohydrate diet find it even more difficult. It is possible just not very practical for the average person and we need healthy eating advice that’s practical. This is the main reason why I am very careful with low carbohydrate diets.
As for fat well I think it’s important to wait for the SACN report. The committee are looking at the whole range of research evidence and will base their findings on the most robust studies. They will take evidence from studies that demonstrate cause and effect (which tend to be short and often don’t reflect the realities of everyday life) and consider this together with evidence from robust, prospective population studies which look at associations between diet and ill health in specific populations over time in real life settings. Taking evidence from these two types of studies together and looking only at studies that were conducted to a very high standard will give us the best understanding of the current evidence.
It is important to look at whether there are interactions between fat and in particular saturated fats and other nutrients in the diet and whether the combination of foods we eat might be important. It is also important to consider whether there are any differences between different types of saturated fats in terms of risks to our health. So it is all pretty complex and at the end of the day we need to give advise that people can apply to their everyday lives. If the advice is complex people tend to give up.
When I meet clients who want to increase their fat intake and reduce their carbohydrate intake I analyse their diets carefully to make sure they are still getting enough fibre and to make sure they are getting enough cereal fibre. For this reason I don’t recommend very low carbohydrate diets. I also advise people to increase the omega 3 fats in their diets from oily fish, nuts and seeds, as there is evidence that this reduces our risk of heart disease, stroke and cancer. Because we know that too much red meat increases our risk of cancer I suggest having it just once a week and I advise people to stay away from processed meats like sausages and bacon as much as possible as again these are associated with an increased risk of cancer. As regards milk and dairy I usually recommend the low fat versions at the moment. This is because a couple of portions of dairy foods each day is the easiest way to meet our calcium requirements and I find that many people end up having too many calories if they use full fat dairy foods, although it will be interesting to see what the SACN concludes.
So please don’t ditch the wholegrain cereals and start eating fatty meats and frying all your foods. It will be really interesting to see what the SACN concludes and I will blog more then on what the report means in practice.