SACN report on lowER carb diets for T2D

Executive Summary

- In March 2020, SACN, the UK Scientific Advisory Committee for Nutrition, invited submissions for a consultation about lowER carbohydrate diets for adults with type 2 diabetes (T2D). I submitted a response, which is included in this note.

- The final report has just been published. It concluded that a lowER carb diet can be recommended by clinicians as a short-term option.

- There were five flaws with the consultation document, which have not been addressed:

• Flaw 1 – The committee members have conflicts of interest in favour of low-fat high-carb diets. Most members have established (and largely unfavourable) views on low-carb diets.

• Flaw 2 – The rational for the review was given as Public Health England asked us to review this because low-carb diets are increasingly being promoted. The committee then rejected the evidence from the physicians and academics promoting these diets.

• Flaw 3 – Examining lowER vs low is a significant flaw. The committee members showed that they know the definition of low carb, but then did not study low carb. LowER carb was carbohydrate comprising 13-47% of total energy and highER carb was 41-55% of total energy. They overlapped.

• Flaw 4 – The report contained a section on carbohydrates, which showed that the committee knows that all foods that contain carbohydrate contain glucose and that glucose is the issue for people with T2D and yet they continue to favour high-carb diets.

• Flaw 5 – If only the same bar had been set for the introduction of low-fat, high-carb guidelines. The rationale for only recommending low-carb diets in the short term (“up to 6 months”) was given as – we don’t know the long-term implications of lowER carb diets. We do know the long-term implications of low-fat diets and they are serious and yet these are still recommended.

- This is too serious an issue for a committee to be reticent to advise people who can’t handle glucose to avoid glucose – and long term.