For a lot of young adolescents, school lunch brings up images of mystery meat and cold vegetables.

But for the 22 million children who participate in the school lunch program, it may be their only guaranteed meal of the day.

Officially, 1 in 5 US children don’t know when their next nutritious meal will be (also known as being food insecure). Over a third of these children live in low-income, single-mother households.

Food insecurity is a serious problem in the United States, particularly for low-income families, children, and the elderly. Many of them live in what we call food deserts (living more than a mile from a grocery store) or food swamps, which is characterized by having an overabundance of fast food options. Deserts and swamps make it particularly hard for low-income people to access healthy food.

Low-income parents rely on schools to provide nutritious meals for their kids —  some kids even receive all three meals of the day from school if they attend after-school programs —  since parents who teeter on the Federal Poverty Line are often working long hours, maybe with multiple jobs.

Going to school hungry can make it extremely difficult to concentrate in school (not just because of distracting weird stomach groans). For example, kids who are experiencing an iron-deficiency may be falling asleep in class. There can be larger implications too. Consistent hunger affects the developmental process since key nutrients are needed in the diet (such as Vitamin A and Zinc) for cell communication and growth, and proper immune function. Because kids are growing, they require more food and more nutrients for proper development.

Thus, kids who are food insecure are more likely to get sick (missing those immune system nutrients) and experience higher rates of behavioral problems such as fighting, hyperactivity, aggression, anxiety, mood swings and bullying. Being hangry is no joke.

Just as certain nutrients are essential for children’s health, the elderly are vulnerable to nutritional deficiencies as well. In comparison to other high-income countries, the United States has a way bigger proportion of older adults who are food insecure (17% compared to 8 or 9% in the UK and Australia). Notably, older women stop producing estrogen which puts them at greater risk of calcium deficiency and osteoporosis. Proper nutrition for older adults can help prevent many diseases such as dementia, cancer, and diabetes.

This is why programs like Meals on Wheels and others for after school can be so important. They help to ensure that vulnerable populations like children and the elderly have access to nutrient-full meals. Even if it costs money now, it saves us money in the long-run through disease prevention and better work productivity.

Some of the school grants proposed to be cut not only help improve food access to food-insecure school kids but provide better quality food too. For example, grants fund farm-to-school programs, salad bars in the cafeteria, cooking programs, and school gardens.

With 75% of primary school teachers saying they regularly see students come to school hungry, a cut in funding for these programs is even scarier than mystery meat.