5 foods that may raise the odds of dementia

More than 6 million Americans are living with dementia. As the population gets older and conditions associated with dementia, such as obesity, continue to rise, that figure is projected to double by 2060.

Although aging cannot be avoided and is the biggest single risk factor for dementia, people are not helpless. Several lifestyle choices can influence whether the disease develops or is delayed, and diet is one of the most important.

A healthy, balanced eating pattern matters most overall, but research also points to certain foods that may increase the chance of dementia when they are consumed too often.

1. Processed meats such as bacon, sausage, hot dogs and deli meat

Even a small amount — about 25 grams a day, or roughly two slices of deli meat — has been linked to a 44% higher risk of all-cause dementia and a 52% higher risk of Alzheimer’s disease, according to a 2021 study. Alzheimer’s is the most common form of dementia.

That does not mean all red meat must be avoided. The same researchers found that unprocessed meat, such as whole cuts cooked from raw, was tied to lower risk.

The difference may come down to nutrition: unprocessed meat provides more protein and iron, while processed meat tends to contain more sodium and saturated fat, along with inflammatory effects in the brain.

2. Sugar-sweetened drinks such as soda, sweet tea and sugary fruit beverages

The more sugar-sweetened beverages you consume, the greater the risk of Alzheimer’s appears to be. A 2025 review found that higher intake was associated with a 49% greater risk.

This category includes colas, ginger ale, fruit drinks with added sugar, sports drinks, energy drinks, and coffee or tea prepared with sugar.

Even drinks sweetened with artificial substitutes, such as zero-calorie or sugar-free options using aspartame, were linked to a 42% higher risk of Alzheimer’s.

Another study suggests sugar may interfere with the way brain cells use energy and function.

3. Fried fish

Vascular dementia, the second most common type, develops when blood, oxygen and nutrients cannot properly reach the brain because blood flow is reduced or blocked.

In a 2024 review, researchers examined several foods to identify which ones were associated with greater risk. Fried fish stood out: eating just 0.25 to 2 servings a week was linked with increased risk.

The review also found that people who ate more ultra-processed foods — especially sugar-sweetened beverages and processed meat at more than two servings a week — had a higher risk of vascular dementia.

On the other hand, lower risk was seen among people who ate more fruits and vegetables, drank more coffee and tea, consumed moderate alcohol intake of 1 to 3 drinks a day, or followed a plant-based diet.

4. Refined carbohydrates such as white bread, pastries and pasta

Carbohydrates account for more than half of many diets, but the type chosen can make a difference.

Refined carbohydrates such as white bread, rice, pasta and breakfast cereals are processed to remove fiber and nutrients, and they are digested quickly, causing blood sugar spikes.

A 2025 study found that frequent intake of these processed carbs was associated with a higher dementia risk. Animal research also suggested that refined carbohydrates may raise the risk of dementia and Alzheimer’s.

By comparison, foods that digest more slowly — including whole grains, fruits and beans — are lower on the glycemic index and may help protect against dementia, according to the same research.

5. Saturated fat

The more saturated fat you eat from sources such as fatty red meat, dairy products, pastries and fried foods, the greater the risk of Alzheimer’s and dementia appears to be.

Even small amounts matter. A 2018 study found that every 4 grams of saturated fat a day — less than a teaspoon of butter — was linked to a 15% higher risk of Alzheimer’s. The group that ate the most saturated fat had about twice the risk of the group that ate the least.

Researchers suggest saturated fat may increase harmful proteins in the brain and contribute to inflammation.