How to tell if you need more fat in your diet?

October 11, 2025 •

4 min read

Fats are a source of essential fatty acids that the body cannot produce on its own and are crucial for absorbing vital fat-soluble vitamins, including A, D, E, and K. So, if you're asking, 'How to tell if you need more fat in your diet?', observing certain physical and mental symptoms is the first step toward assessing your nutritional needs.

Quick Summary

Recognize the signs of insufficient dietary fat, such as persistent hunger, fatigue, dry skin, and brain fog, as fat is essential for energy, cell health, and vitamin absorption. Incorporating healthy sources like nuts, avocados, and fatty fish can help rectify these issues and improve overall wellness.

Key Points

Dry Skin and Hair: Flaky, dry skin and brittle hair can indicate your body lacks the essential fatty acids needed for hydration and cell structure.
Persistent Fatigue: As fat is a dense energy source, a deficiency can lead to low overall calorie intake and constant feelings of sluggishness and fatigue.
Brain Fog: Omega-3 fatty acids are vital for cognitive function, and low intake can result in poor memory, difficulty concentrating, and general mental fogginess.
Constant Hunger: Fat promotes satiety and slows digestion; without it, you may feel hungry shortly after eating meals.
Joint Pain and Frequent Illness: A lack of omega-3s can increase inflammation, contributing to aching joints and a weakened immune system.
Vitamin Absorption Issues: A fat-deficient diet impairs the absorption of fat-soluble vitamins A, D, E, and K, leading to potential deficiencies and related health problems.

The Surprising Signs of Insufficient Dietary Fat

For decades, fat was demonized in the diet world, but modern nutritional science has highlighted its essential role in bodily functions. Healthy fats are not just for energy; they are fundamental for hormone production, cell growth, brain function, and nutrient absorption. Spotting the signs of a fat deficiency can be the first step towards a more balanced and healthy diet.

Your Skin, Hair, and Nails are Showing Symptoms

One of the most visible indicators of low fat intake manifests on the outside of your body. Your skin, which relies on fatty acids to maintain its moisture barrier, can become noticeably dry, flaky, or inflamed. This can even lead to skin conditions like dermatitis. Similarly, hair can become dry, brittle, and even prone to hair loss if your diet lacks sufficient essential fatty acids. Brittle nails are another tell-tale sign that your body isn't receiving enough of these crucial nutrients.

Persistent Hunger and Fatigue

If you find yourself constantly hungry, even shortly after meals, it could be a sign you need more fat. Fat is a slow-digesting macronutrient that provides a lasting feeling of satiety and fullness. When meals are low in fat, they digest quickly, leaving you feeling unsatisfied and reaching for snacks. Additionally, fat is a dense source of calories (9 per gram, compared to 4 for carbs and protein). A low-fat diet can lead to an overall calorie deficit, resulting in persistent fatigue, low energy, and sluggishness.

Cognitive Issues and Mood Swings

Your brain is about 60% fat, making essential fatty acids, especially omega-3s, critical for proper function. If you're experiencing "brain fog," difficulty concentrating, or poor memory, it could be linked to an inadequate intake of healthy fats. Mood imbalances, including irritability and anxiety, can also be associated with a lack of omega-3s, which are known to support mental health.

Frequent Illnesses and Joint Pain

Omega-3 fatty acids play a significant role in reducing inflammation and supporting the immune system. A lack of these fats can weaken your immune response, making you more susceptible to frequent colds and infections. Furthermore, omega-3s help maintain the structural integrity of cells throughout the body, and a deficiency can lead to joint pain, stiffness, and inflammation.

The Crucial Role of Fat-Soluble Vitamins

Fat is essential for the absorption of fat-soluble vitamins: A, D, E, and K. A deficiency in these vitamins can lead to a cascade of health issues. For example, inadequate vitamin A absorption can cause vision problems like night blindness, while insufficient vitamin D can affect bone health.

How to Introduce More Healthy Fats into Your Diet

Instead of focusing on restrictive low-fat diets, shift your attention to incorporating healthy, unsaturated fats. Here are some simple ways to increase your intake:

Include fatty fish: Opt for salmon, mackerel, or sardines at least twice a week.
Snack on nuts and seeds: A handful of walnuts, almonds, chia seeds, or flaxseeds can boost your omega-3 and healthy fat intake.
Embrace avocado: Add sliced avocado to salads, sandwiches, or mash it for toast.
Cook with healthy oils: Use extra-virgin olive oil, canola oil, or sesame oil for cooking and dressings.
Choose full-fat dairy: If you tolerate dairy, full-fat yogurt and cheese are good sources of fat.

Healthy vs. Unhealthy Fats: A Comparison Table

It's important to differentiate between the types of fats in your diet. Not all fats are created equal, and their impact on your health varies significantly.


Feature	Healthy Fats (Unsaturated)	Unhealthy Fats (Saturated/Trans)
Source	Plant-based foods, nuts, seeds, avocados, and fatty fish.	High-fat dairy, red meat, processed snacks, fried foods, and some tropical oils.
Health Impact	Lowers bad (LDL) cholesterol, increases good (HDL) cholesterol, reduces risk of heart disease, supports brain function and reduces inflammation.	Increases bad (LDL) cholesterol, raises risk of heart disease, contributes to inflammation and insulin resistance.
Types	Monounsaturated fats (MUFAs) and polyunsaturated fats (PUFAs), including Omega-3s and Omega-6s.	Saturated fats and artificial trans fats.
At Room Temp	Typically liquid (e.g., olive oil).	Typically solid (e.g., butter, lard).

Conclusion

Ignoring your body's signals can impact your long-term health. If you notice a combination of symptoms like dry skin, persistent fatigue, brain fog, or frequent hunger, it might be time to reassess your dietary fat intake. Remember that not all fats are bad, and incorporating the right kinds—the healthy, unsaturated ones—can significantly improve your energy levels, mental clarity, and overall well-being. By making simple, conscious choices to add more healthy fat sources to your meals, you can nourish your body and reverse the signs of deficiency. For more specific dietary advice, especially if you have underlying health conditions, consult a healthcare professional or a registered dietitian.

This article is for informational purposes only and does not constitute medical advice. Consult a healthcare professional before making significant changes to your diet.

Frequently Asked Questions

Among the first and most common signs are skin problems, including dryness, flakiness, or inflammation, along with unexplained fatigue and persistent hunger shortly after meals.

Yes, insufficient intake of essential fatty acids, particularly omega-3s, is linked to cognitive issues like brain fog, poor memory, and mood imbalances such as anxiety and low mood.

Fat is crucial for the absorption of fat-soluble vitamins (A, D, E, K). Without adequate fat in your diet, your body cannot efficiently absorb and utilize these essential vitamins, leading to potential deficiencies.

No, not all fats are equal. Healthy unsaturated fats (monounsaturated and polyunsaturated) found in plant-based foods and fatty fish are beneficial, while saturated and trans fats found in processed foods should be limited.

Excellent sources of healthy fats include avocados, nuts (almonds, walnuts), seeds (chia, flax), olive oil, and fatty fish like salmon and mackerel.

Ironically, yes. Low-fat diets often lead to consuming more refined carbs and sugars to feel full, which can contribute to weight gain. Healthy fats promote satiety, helping with weight management.

Healthy unsaturated fats typically come from plant-based sources and are liquid at room temperature (like olive oil). Unhealthy saturated and trans fats are often found in animal products and processed foods and are solid at room temperature (like butter or lard).