Question: What qualifies as a 'quality' source of protein and does the protein source really matter?
A recent fitness trend has many people focusing on consuming protein-rich foods, while restricting their intake of carbohydrates, to get leaner or manage body composition.
On the back of this, many food companies are now labelling their products as a 'good source of protein' or 'high in protein' to attract buyers. However, just because a food label states that it is a source of protein, doesn't mean that it is necessarily a good food choice or a good quality source of protein.
For example, many processed meats contain added sugars, flavour enhancers, salts and preservatives that should be minimised in the diet. An example of a quality animal source of protein would be a whole piece of sirloin steak or fresh wild fish; whereas breaded, farmed fish is a poor source of protein.
In the case of plant sources of protein lentils, oats, shelled hemp seeds and unsalted or heated nuts and seeds are good quality protein sources. Nuts and seeds that have been salted and roasted in vegetable oil are bad protein options.
Quality protein can, therefore, be sourced from both animal- and plant-based foods. However, it is also worth remembering another term often used when describing protein – a complete or incomplete protein.
A complete protein (mostly animal sources) contains all of the essential amino acids that the body needs, whereas an incomplete protein (often plant sources) is missing one or more of these essential amino acids.
However, you should not confuse an incomplete protein with being a poor quality source of protein, but rather have variety in your food choices to ensure you get a large range of amino acids in your diet.
QUESTION: FOODS CONTAINING ADDED SUGARS SHOULD BE AVOIDED WHERE POSSIBLE, BUT WHAT IS AN ACCEPTABLE AMOUNT?
In terms of general health, and the risk for metabolic disease, foods containing added sugars are probably the worst options you can choose.
Just to be clear, foods with added sugars are vastly different to foods containing natural sugars (often fructose) such as fruits and certain vegetables. Jam, yoghurts, cereals, fruit juice and bread are foods that commonly contain added sugars.
When you are going to choose a food with added sugar, what is an acceptable amount of added sugar in a food? Robert Lustig, who is well known for his work in raising awareness about the risks of over-consumption of refined sugar, believes that a daily intake of 50 grams of sugar should be the upper limit for most people. This is broadly in line with recent recommendations from the World Health Organisation; it suggested that sugar should only account for 5pc of our daily energy intake.
With this in mind, the best option is to sweeten foods yourself with fresh fruit or a little honey. Foods that are minimally processed and contain a small amount of added sugar (five to 10g per 100g) can, from time to time, be consumed in small amounts, but like most things it really depends on how active you are.
QUESTION: WHAT IS AGAVE NECTAR AND IS IT HEALTHY?
One of the claims around agave is that, because of its high fructose content, it has minimal effects on the sugar levels in the blood (measured as another sugar known as glucose). This is probably too simplistic a viewpoint as we now know that fructose can have many effects independent of effects on glucose concentrations.
Agave nectar that has been minimally processed can be used in small amounts to sweeten foods, but many commercially available agave nectar products are highly refined.