Coffee is often the go-to drink for boosting energy and mental clarity, but not all coffee is created equal. Many of us opt for a cup in the morning to stay awake, but some coffee additions could actually be doing the opposite!
While caffeine can help improve focus, certain ingredients commonly added to coffee may actually contribute to brain fog instead of fighting it. These additives can cause blood sugar spikes, inflammation, and even dehydration, all of which can leave you feeling sluggish and unfocused.
We checked in with Ro Huntriss, RD and Chief Nutrition Officer at Simple App, to discover two popular coffee ingredients you should avoid because they can exacerbate brain fog. According to her, sugar and creamer are the ones to steer clear of. Read on to learn more.


1. Sugar
Ro says that when it comes to brain fog, "although not a medical condition, it’s often used to describe a group of symptoms related to brain function, including poor concentration, memory problems, mental fatigue, confusion, and difficulty in finding words."
Sugar can negatively impact various aspects of overall health, including brain function. One of its lesser-known effects is its potential to harm cognitive health.
"Studies have shown that consumption of added sugar, in particular sugar-sweetened drinks, is associated with reduced cognitive function and memory issues. Furthermore, following sugar consumption, you can experience an energy spike followed by a crash, which may influence your energy, which has the potential to impact mental fatigue," Ro explains.

2. Creamer
Coffee is hard to enjoy without creamer; many popular and viral coffee drinks rely on it. However, these creamers don’t just add extra calories—they can also contribute to sluggish mental focus.
"There are a variety of different creamers available, but the ones that are most commonly associated with symptoms of brain fog are those that contain added sugar. Powdered creamers can have added sugar, and liquid flavored creamers are often high in sugar too. With these drinks, particularly if consumed in excess, they can contribute to reduced cognitive function as above," she notes.
Better alternatives
Fortunately, there are many healthier alternatives that support focus while being lower in calories and sugar.
For sugar, Ro recommends cinnamon (read more about the benefits of cinnamon here!). "Cinnamon adds a natural sweetness without the sugar or calories. Because it is high in antioxidants, it can actually support brain health and cognitive function, so it’s a great alternative."
As for creamer, a plant-based swap is best for those who still prefer a creamy texture. "Unsweetened oat milk offers a low-calorie option to a traditional creamer whilst still offering a creamy texture. Whilst creamers can be high in saturated fat and/or sugar, unsweetened oat milk isn’t high in either and is a source of beta-glucans, a type of fiber that can not only support heart health but can also reduce the impact of glucose spikes, reducing the risk of energy crashes too."
If you've been keeping up with the health and wellness industry, you've probably heard about the negative buzz around oat milk, but Ro clarifies, "Oat milk can sometimes be unfairly villainized, but an unsweetened oat milk is a great creamer alternative and can reduce symptoms associated with higher-sugar alternatives. Choosing fortified versions means that your oat milk can be further enriched with vitamins and minerals that can support wider health."
One of our favorite editor-approved creamer brands is Califia Farms’ Simple & Organic line that’s "USDA Certified Organic and made with simple ingredients and no gums or oils." Shop here!