Food fight: Row over saturated fat advice
A row has erupted over claims that official guidance to cut down on saturated fat had been based on shaky evidence.
In the 1970s and 80s, there was a big push away from saturated fats in the US and UK as experts cautioned they were bad for the heart.
Scientists writing in the journal Open Heart have now argued this advice lacked the solid scientific trials needed to back it up.
But many experts have come to the defence of the original guidelines.
Prof Christine Williams, at the University of Reading, says the claim that evidence was insufficient is "misguided and potentially dangerous".
And in recent years there has been more scientific data supporting the case that saturated fat is bad for health.
Public Health England say current recommendations, to keep fat consumption to a maximum of 30% of overall energy intake and saturated fat to just 10%, should be followed to maintain a healthy diet.
But is this spat over a single food type a red herring? Is it leading us down a dangerous dietary path?
What is a healthy diet?
One thing experts agree on is that balance is key to a good diet.
Modern nutritional advice makes clear that no one nutrient or food type is the outright villain - simply avoiding fat or excluding sugar or cutting out carbohydrates is not the answer to keeping well or shedding pounds healthily.
And most dieticians agree there is no such thing as a super food. No single food - however exotic - can provide all the nutrients we need.
So what should we make sure is on our plates?
Plenty of fruit and vegetables
These types of foods are important sources of vitamins and minerals - key to both growth and repair.
UK guidelines suggest eating around five portions of fruit and vegetables a day.
To help achieve this, nutritionists advise swapping a mid-morning snack for fruit, or add a banana to breakfast cereal.
But a debate is now emerging over fruit juices. They do not always contain the fibre found in whole fruit and veg.
And there are increasing concerns that they often come packaged with added sugar, piling on unnecessary calories and leading to tooth decay.
Current recommendations suggest drinking no more than one glass of juice every day.
Some bread, rice, pasta and other starchy foods
Experts say starchy food should make up around a third of the food we eat.
And they recommend swapping to wholegrain varieties when possible to increase the amount of fibre in our diets.
Though some people think starchy food is fattening, gram for gram the carbohydrate they contain provides fewer than half the calories of fat, says NHS Choices.
Add in some meat, fish or lentils
Protein is an important part of a healthy diet. Everything from our hair, muscles, skin and nails needs protein to build and repair itself.
Even if you don't eat meat, your meals should still contain other sources of protein, such as lentils or nuts.
And when cooking meat, lean cuts are best - trim away visible fat when possible.
Recent advice also suggests people should aim for two portions of fish a week - including one serving of oily fish.
Oily fish contains omega-3 fats, which may help prevent heart disease.
What about milk and dairy?
Because they're good sources of protein and calcium, milk and dairy products can form part of a healthy diet.
But they should be eaten in moderation. Cheese can contain lots of salt and fat, for example.
Not too much fat, salt or sugar
Treats can be a good thing - once in a while. But too many and you face trying to burn off lots more calories than you need.
If they aren't burnt off they can lead to weight gain.
According to official surveys, most people in the UK eat too much sugar.
For example, sugary drinks, including alcoholic ones, are often high in energy and when consumed too frequently, can pile on the pounds.
A number of experts now argue the best way to get all of this advice on to one plate is to cook up a Mediterranean style meal.
The Mediterranean diet has been repeatedly linked to health gains, such as cutting the risk of heart disease.
Typically, it consists of an abundance of vegetables, fresh fruit, wholegrain cereals, olive oil and nuts, as well as poultry and fish, rather than lots of red meat and butter or animal fats.
Reaching for the ready meal
People often think of ready meals, takeaways and pizzas as processed food.
And in recent years, people have been urged to cut their intake of this type of foods, which are often high in saturated fats, sugar and salt.
But it's worth checking labels before throwing them all in the bin. Some convenience foods may still contain good nutrients and be fine to eat in moderation.
A can of baked beans, for example, contains both fibre and protein.
There is no one-size-fits-all recipe for a good diet. And your nutritional needs depend partly on your age and how much activity you do.
But what is clear as obesity levels rise is no single food type can shoulder all the blame.