Most peo­ple under­es­ti­mate how much they eat and under­es­ti­mate their calo­rie intake by 20 to 50 per­cent, mak­ing it dif­fi­cult to main­tain a healthy weight. But no one wants to deceive any­one, there are phys­i­o­log­i­cal rea­sons for this.

Peo­ple actu­al­ly think they ate 1 cook­ie and not 5, the high­er the weight gets, the big­ger the error becomes.

Research has shown time and time again that peo­ple have a high ten­den­cy to under­es­ti­mate what they ate through­out the day and tend to under­es­ti­mate the caloric con­tent of their foods. This is not just one study; a decent num­ber of them have already been accu­mu­lat­ed.

Accord­ing to a Cor­nell Uni­ver­si­ty study, every­one does it. Peo­ple of nor­mal weight under­es­ti­mate caloric intake by about 20 per­cent, and over­weight peo­ple under­es­ti­mate by about 40 per­cent. Oth­er sources say the fig­ure is clos­er to 50 per­cent.

By self-esti­ma­tion, peo­ple on aver­age make about 15 deci­sions relat­ed to food and drink every day. But the truth is that we make more than 15 times that number—more than 200 of these deci­sions.

Understand our brain

An arti­cle in Fron­tiers in Psy­chol­o­gy (2019) points to deficits in a crit­i­cal area of ​​the brain respon­si­ble for learn­ing, mem­o­ry, and cog­ni­tion: the hip­pocam­pus and asso­ci­at­ed overeat­ing. The paper presents evi­dence that sug­gests dys­func­tion in the hip­pocam­pus may lead to deficits in food recall, sen­so­ry expe­ri­ence, and sati­ety. Mem­o­ry dys­func­tion may mean that a per­son does not use mem­o­ries to under­stand what they have eat­en before and apply that expe­ri­ence to future deci­sions.

What affects our memory?

“Western” diet

The West­ern diet is syn­ony­mous with lots of processed and high-calo­rie foods. This is the kind of food we tend to down­play. Research also shows which foods we most often under­val­ue:

  • Cake
  • Snacks: chips, pop­corn
  • Cheese
  • French fries
  • Soft drinks
  • But­ter and sauces

Meal size

Peo­ple do not accu­rate­ly eval­u­ate large objects. The larg­er the por­tion of food, the less accu­rate­ly we esti­mate how many calo­ries it con­tains. This makes it clear why over­weight peo­ple can be mis­tak­en by 40 and 50 per­cent. Their por­tions are larg­er, which means they are more dif­fi­cult to esti­mate and there is more error.

What solution?

  • Switch to a healthy, bal­anced diet of whole grains that are dif­fi­cult to overeat.
  • Food diary:
  1. It helps devel­op mind­ful­ness and aware­ness by reduc­ing envi­ron­men­tal dis­trac­tions.
  2. Gives a more crit­i­cal look at the amount of food eat­en.
  3. Helps build eat­ing habits and behav­ior pat­terns.
  4. Can be a way to con­sid­er the neg­a­tive con­se­quences of food choic­es or por­tions.


I count calo­ries, but I don’t lose weight: what is the real rea­son?

It’s All About the Size: Con­trol Por­tions With­out Count­ing Calo­ries