A study of 1,000 16-25 year-olds found 53 per cent of females said they did not eat certain types of food because they thought they would look better for it.
And 55 per cent even admitted to occasionally skipping entire meals, with two-fifths of those doing so in order to keep their weight down.
One-third of participants first cut important foods from their diet between the ages of 14 and 16, while almost one in 10 were as young as 10 years old.
The study by Arla Goodness found one in five respondents had removed dairy from their diet, making it one of the most likely food groups to be cut.
Nutritionist Lucy Jones said: “Certain food groups provide crucial nutrients that can help support a healthy lifestyle, so removing them can have unwanted health effects that many may not be aware of.
“Dairy, in particular, is important for young growing girls as calcium supports the maintenance of normal bones and teeth.”
The poll also found more than one-quarter (26 per cent) of those who had eliminated food groups from their diet were influenced by those around them.
More than one-third (36 per cent) looked to fashion and lifestyle influencers and celebrities on social media for inspiration.
Despite dairy being beneficial as part of a healthy balanced diet, 44 per cent of young women thought the food group was unhealthy or had a negative impact on their body image.
It comes after data from Public Health England showed that 22 per cent of girls aged 11-18 are not consuming enough calcium to meet minimum dietary requirements.
As a result, the number of female teenagers with very low calcium intakes has significantly increased from 2008 to 2017.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies