Saturated fats and health: SACN report
The SACN Report “saturated fats and health 2019” is a comprehensive review of the evidence linking dietary fat intake and health. Based on 47 systematic reviews and meta-analyses, the evidence demonstrated that higher saturated fat consumption is linked to raised blood cholesterol and increased risk of heart disease. The recommendation therefore, to reduce saturated fat intake to no more than 10% of total dietary energy intake, is clearly in the right direction. However, we are left with questions over the expected quantitative benefit on cardiovascular outcomes of reducing saturated fat intake from an average of about 12.5% of energy intake in adults, where we are now, to 10% and whether 10% goes far enough.
It is known from observational studies supported by randomised controlled trials, that reducing LDL cholesterol by about 1mmol/L reduces the risk of fatal and non-fatal ischaemic heart disease events (mainly heart attacks) by about 40%. But what is unclear from this report is how many mmol/L LDL cholesterol is likely to be lowered by reducing saturated fat from 12.5% to the recommended 10% of dietary energy intake. Translating % energy intake into units that allow measurable effects on health outcomes is unclear, leaving a lack of clarity over the magnitude of benefit.
It is also unlikely that reducing saturated fat intake, which lowers LDL cholesterol, would have an effect on nonfatal cardiovascular outcomes but no effect on fatal cardiovascular disease outcomes, as concluded in the report. A useful health intervention usually has consistent effects on both fatal and non-fatal outcomes, providing there are no serious toxic effects, and the SACN report concluded that reducing saturated fats is unlikely to increase health risks for the UK population. Methodological issues in the studies assessed, such as a dilution through non-compliance with a dietary regimen in randomised trials or a narrow window effect (small difference between comparator groups in observational studies) may be limiting the statistical power in such studies to show consistent effects across fatal and non-fatal cardiovascular outcomes. Therefore, the lack of an effect of reducing dietary saturated fat intake on fatal cardiovascular disease outcomes should not be interpreted as there being no beneficial effect.
Notwithstanding these scientific issues, the SACN conclusion that saturated fats should be reduced and swapped for unsaturated fats in our diet is welcomed. The challenge is now for the food industry to implement these recommendations and voluntarily reformulate processed foods to for the health of the nation.
Professor of Cardiology
Barts and the London School of Medicine
If you would like to reduce saturated fat in your diet, try our free smartphone app FoodSwitch. FoodSwitch allows users to scan the barcode of a product and see healthier alternatives, all of which are displayed with front of pack colour coded information on fat, saturated fat, sugars and salt, making it easier to see at a glance, which product is healthier. FoodSwitch also has a ‘FatSwitch’ filter to help you switch to similar foods with lower levels of saturated fats.
Other useful tips to reduce your saturated fat intake:
- Use less full fat dairy products, or switch to lower fat versions e.g. semi-skimmed, 1% or skimmed milk, reduced fat cheese and vegetable based spreads instead of lard or butter
- White fish, chicken and turkey (without skin) are lower in fat, as are lean cuts of red meat with visible fat and skin removed. Oily fish (such as mackerel, sardines and salmon) are high in good fats and should not be cut out from your diet.
- Bulk up meat dishes with more vegetables, which are low in saturated fat. This will reduce your meat consumption and increase your vegetable intake, which are high in vitamins and minerals, a double benefit to health
- Use less fat in cooking by using smaller amounts, spraying oils, or reduced/low fat spreads.
- Grill, microwave or bake foods instead of frying and roasting.
- Fats and oils richer in monounsaturates (e.g. rapeseed oil, olive oil) or polyunsaturates (e.g. corn oil sunflower oil) should be used sparingly as substitutes.
To view the full report click here
1 August 2019