Portion distortion – Knowing how much is too much

It is widely known that when people are exposed to larger portions they eat more,¹ and it would seem that nowadays, we have lost all sense of what the right proportion of food to consume is. We are constantly bombarded with king-size packs of foods in supermarkets, oversized meal portions in restaurants and at home,  it can be a problem too with fancy dinner plates urging us to pile on more food.

A 2003 US study² found that since the 1970s, portion sizes have been on the increase, with Europe following a trend led by the US. This study found that 21st century portion sizes of popular foods add an extra 50 to 150 calories. Take a simple scone for example. They are now four times bigger than the standard 48g scone. Add a latte to that and you could be consuming up to 700kcal. This is no longer a ‘snack’ because it contains more calories than a standard meal. 

For every extra unnecessary 100 calories a day added to meals or snacks, this can pack on an extra 10lbs of weight a year. A digestive biscuit has increased in size by 17% since 1993, which would add 3,330 calories to a person’s diet each year.  From a food manufacturing point of view, on average between 1993 and 2013, several food types have increased in size:

• Shepherd’s pie ready meals almost doubled in size

• Bagels increased in size from 70g to 86g

• A family pack of crisps increased 50% from 100g to 150g

• A portion of peanuts is now 80% larger

• An individual chicken pie is now 40% bigger.

Consumer awareness

We are exposed to large portion sizing that is driven by ‘value-size pricing’, which the food industry needs to take responsibility for. Many consumers are not aware that portions have been getting bigger, but acknowledge that self-regulation of portion size is extremely difficult and a major obstacle when it comes to weight management. 

Interestingly, despite increases in intake, individuals presented with large portions generally do not report or respond to increased levels of fullness, suggesting that hunger and satiety signals are ignored or overridden. However, as a dietitian working with weight management clients in the clinic, I have found that when clients eat satisfying portions of low-energy-dense foods (ie. more vegetables/salad), these can help to enhance satiety and control hunger while restricting energy intake for weight management.

Notice how crockery at home consists of large bowl and plate sizes that are 28cm diameter rather than 25cm. Everything seems to be getting bigger and so we become accustomed to larger portions becoming the norm, distorting how we think about serving size and what the right amount is. 

We only have to walk into an antique shop to see the dinky wine glasses and delicate little plates that resemble saucers which used to be actual glass and dinner plate sizes in the past.

Of course, all consumers could take the initiative to use smaller plates, but people often don’t, or if they do, more than half of their plate is made up of starchy carbohydrates such as rice, pasta and potatoes. Developing coping strategies, like portion plates for the home and workplace, in order to avoid overeating in such environments are known to help modulate how much is eaten.³

Dietitian’s role

It is not good enough as dietitians to be saying eat plenty of vegetables and have a little less rice or pasta. People need specifics to help maintain a healthy weight, and they need these specifics to be practical and logical to understand. 

As dietitians, if we say that 60g of uncooked rice or pasta is a portion, then what does this look like without the calorie crunching or taking out the weighing scales? Things like rice and pasta are very difficult to judge because they look so different in the cooked and uncooked state. Uncooked pasta, spaghetti, rice and quinoa should weigh about 50 to 60g, which equates to a cooked weight of about 150g (or the size of a tennis ball). Two potatoes as a portion should look like two egg sized portions.

People think they have the knowledge and that they will not fall into the trap of eating more, but unfortunately, they do eat more. In fact, it seems that the only people who are immune to falling into this trap are young children. 

Fisher⁴ demonstrates that before the age of three to four, children have the ability to know when they are full and to stop eating. However, after this age, self-regulation of hunger is lost and as a result of parents serving adult portion sizes to their children, combined with the fact that the food may be energy-dense (chicken nuggets, chips etc...), children end up eating too much and it can be extremely difficult to break this habit. Of course, it is human nature to eat what you are presented with, therefore potentially overeating. 

As well as increasing portions and plate sizes, clients often report that when they were children, their parents told them to clear their plates, but is associated with heavier body weights.⁵

The problem is no one likes the concept of ‘less’. We yearn for overflowing glasses and an abundance of food on our plates or on the table. One of the simplest ways around this is to take away the larger plate and replace it with a smaller one. If people can take control of this and actually implement the tactic of using smaller crockery to help them understand what portions actually look like, they will eat less, yet their plate will look full with lower energy foods like salad or vegetables. 

Strategies moving forward

The obesity epidemic is multifactorial and does not revolve around portion sizes alone, but we can combine different strategies to help reduce the problem:

• There is the perception that educating on portion sizes is only for dieters and people with special dietary needs. Consumers need the strong voice of dietitians to help empower and educate them to manage portion sizes in the home, restaurants, for snacks, indulgent foods and even correct portion sizing for healthy foods

• Well-funded projects with the use of tools like portion plates, to help equip people with the knowledge to make necessary changes

• Campaigns like Safefood’s portion campaign needs to continue for the messages to sink in. Strategies like children serving themselves at the dinner table may help to allow children to determine how much they will eat

• Also children should not be required to clear their plates nor be rewarded for doing so. Eating as a family, with parents showing a good example, is vital to encourage healthy eating

• The food industry has a lot to answer for.  For example, why not add vegetables to shop bought burgers? That way consumers would still be able to consume a good portion of food, but with less energy and fat

• The abundance of large portions of inexpensive, energy-dense foods in restaurant environments appears to override satiety mechanisms so that individuals consume more energy than is required for physiologic needs. Calorie labelling in fast-food outlets at present show limited evidence of a positive effect, in terms of people purchasing healthier food choices and preventing obesity.

Multifaceted approaches that will involve changes to the current food environment, educational initiatives and participation by individuals are needed to help change food portioning habits.

References

1. Ledikwe JH, Ello-Martin JA, Rolls BJ. Portion sizes and the obesity epidemic. J Nutr. 2005 Apr;135(4):905-9
2. Young LR and Nestle M. Expanding portion sizes in the US marketplace: Implications for nutrition counselling  J Am Diet Assoc. 2003;103:231-234
3. Hollands GJ, Shemilt I, Marteau TM, Jebb SA, Lewis HB, Wei Y, Higgins JP, Ogilvie D. Portion, package or tableware size for changing selection and consumption of food, alcohol and tobacco. Cochrane Database Syst Rev. 2015 Sep 14;(9)
4. Fisher JO. Effects of age on children’s intake of large and self-selected food portions. Obesity (Silver Spring);15:403–12
5. Robinson E and Hardman CA (2016) Empty plates and larger waists: a cross-sectional study of factors associated with plate clearing habits and body weight.  Eur J Clin Nutr. 2016 Jun;70(6):750-2