What Are the Best Foods for Acclimatisation?

At high altitudes, the body's energy requirements increase significantly, with research indicating a higher reliance on carbohydrates for fuel. To help your body adjust to lower oxygen levels and prevent altitude sickness, a strategic diet focused on specific nutrients is crucial.

Quick Summary

Proper nutrition and hydration are critical for adjusting to high altitudes. The right diet emphasizes complex carbohydrates, iron-rich foods, and ample fluids to mitigate altitude sickness symptoms effectively.

Key Points

• Hydration is key: Drink 3-5 liters of water daily, supplemented with electrolytes, to combat dehydration and aid adjustment.

• Prioritize complex carbs: Focus on foods like oats, quinoa, and sweet potatoes for sustained energy and efficient oxygen use at altitude.

• Increase iron intake: Consume iron-rich foods such as spinach and lentils to support red blood cell production and oxygen transport.

• Embrace antioxidants: Berries and leafy greens help fight oxidative stress caused by the lower oxygen levels at higher altitudes.

• Avoid fatty and salty foods: Heavy, fatty meals and excess sodium can hinder digestion and cause dehydration, which worsens altitude sickness symptoms.

• Eat small, frequent meals: As digestion slows down, eating smaller portions more often is easier on your stomach and provides a steady supply of energy.

• Listen to your body: Pay attention to your body's signals, especially appetite changes, and don't force yourself to eat heavy meals.

The Science Behind High-Altitude Nutrition: Why Your Diet Matters

When you ascend to high altitudes, the air pressure drops, meaning there is less oxygen available for your body with every breath. In response, your body undergoes several physiological changes to adapt, including an increase in your metabolic rate and respiration. This causes your body to burn more calories and rely heavily on carbohydrates for energy because they require less oxygen to metabolize. Your gut's ability to digest food also slows down due to reduced blood flow, making it harder to process heavy, fatty meals. Therefore, tailoring your diet to support these changes is a vital part of a successful and healthy acclimatisation process.

Core Pillars of an Acclimatisation Diet

Hydration is Paramount

Increased respiration and the drier air at high altitudes cause you to lose fluids faster, often without feeling as thirsty as you normally would. Maintaining proper hydration is the single most important dietary strategy for acclimatisation.

• Drink consistently: Aim for 3-5 liters of fluid per day, sipping regularly instead of gulping large amounts at once.
• Include electrolytes: Add electrolyte powders or tablets to your water to replenish essential minerals lost through sweat and increased urination.
• Choose hydrating foods: Consume water-rich fruits and vegetables like watermelon, cucumbers, and berries.

Complex Carbohydrates: Your Primary Fuel

Because your body burns carbohydrates more efficiently at altitude, making them the cornerstone of your diet is essential for sustaining energy.

• Load up before ascent: In the days leading up to your trip, focus on carbohydrate-rich foods like whole grains, rice, and potatoes to build up your glycogen stores.
• Pack nutrient-dense options: Good sources include oats, quinoa, brown rice, sweet potatoes, and lentils.
• Consider simple carbs for quick energy: During a strenuous hike, quick-absorbing carbs like dried fruit or energy gels can provide a much-needed boost without upsetting your stomach.

Fueling with Iron and Antioxidants

Your body's primary adaptation to low oxygen is increasing red blood cell production to improve oxygen transport. This process requires sufficient iron.

• Boost iron intake: Ensure you get enough iron by eating foods like spinach, lentils, beans, and lean meats. Pair these with Vitamin C-rich foods to enhance absorption.
• Combat oxidative stress with antioxidants: Higher altitude can increase oxidative stress. Antioxidant-rich foods like berries, dark leafy greens, and citrus fruits can help protect your cells.

Lean Proteins for Repair and Recovery

Protein is important for muscle repair and the synthesis of hemoglobin, the protein in red blood cells that carries oxygen. Choosing lean proteins is important as excessive fat can slow down the digestive process at altitude.

• Sources of lean protein: Include lentils, beans, chicken, and fish in your meals.
• Consider supplements: If your appetite is suppressed, a protein shake might be an easy way to ensure adequate intake.

Foods to Eat and Foods to Avoid

Foods to Embrace for Acclimatisation

• Oats and Quinoa: Excellent sources of complex carbohydrates for sustained energy.
• Bananas: Rich in potassium and easily digestible, helping to replenish electrolytes.
• Dried Fruit: Provides quick energy and is packed with calories in a lightweight form.
• Nuts and Seeds: Great for healthy fats and dense calories, plus they are easy to snack on.
• Spinach and Other Leafy Greens: Packed with iron and antioxidants to aid oxygen transport and combat stress.
• Lentils and Beans: Offer a good mix of complex carbs and lean protein.
• Instant Soups and Broths: Hydrating and easy on the stomach, providing warmth and minerals.

Foods to Avoid During Acclimatisation

• Heavy, Fatty Meals: Can be difficult to digest and increase feelings of nausea.
• Very Salty Foods: High sodium can lead to dehydration, which worsens altitude sickness symptoms.
• Excessive Caffeine: Acts as a diuretic and can lead to dehydration.
• Alcohol: Dehydrates the body and can impair judgment, compounding altitude effects.
• Highly Processed Foods and Sugary Snacks: Lack nutritional value and can cause energy crashes.

Comparison Table: High-Altitude Food Choices

Nutrient Type	Best Food Choices	Foods to Minimize or Avoid
Carbohydrates	Oats, Quinoa, Sweet Potatoes, Brown Rice, Dried Fruit	Sugary drinks, Candy bars, Refined flour products
Protein	Lentils, Beans, Lean Chicken, Fish, Tofu, Protein Powder	Fatty meats, Heavy dairy products
Hydration	Water, Electrolyte Drinks, Herbal Teas, Broth, Coconut Water	Caffeinated beverages, Alcohol, Sugary sodas
Healthy Fats	Nuts, Seeds, Avocado, Olive Oil	Greasy or fried foods, Heavy sauces
Micronutrients	Spinach, Berries, Citrus Fruits, Garlic, Ginger	High-salt processed foods, Artificial flavorings

Practical Eating Strategies for the Mountains

Effective nutrition at altitude is also about how you eat, not just what you eat. Here are a few practical tips to help you manage your diet while acclimatising:

• Eat early and often: Due to suppressed appetite and slower digestion, eating small, frequent meals throughout the day is more effective than three large ones. This keeps your energy levels stable.
• Listen to your body: If a certain food causes discomfort, avoid it. Everyone's body reacts differently to altitude.
• Prioritize warm liquids: Warm beverages like herbal tea or hot cocoa can be soothing and help with hydration and circulation.
• Experiment before you go: Test different foods and meal combinations at home to see what your body tolerates well. This will prevent unpleasant surprises on your trip.

Conclusion: Fueling Your High-Altitude Journey

Acclimatisation is a complex process, but with a smart, food-focused approach, you can significantly reduce the risk of altitude sickness and enhance your overall experience. Prioritizing hydration, complex carbohydrates, and nutrient-rich foods while avoiding fatty, salty, and processed items provides your body with the best fuel for the task. By planning your nutrition carefully and listening to your body's signals, you can ensure your high-altitude adventure is both safe and enjoyable. For more scientific insights into the body's response to altitude, you can consult sources such as the Altitude Research Center.

Frequently Asked Questions

Can you get altitude sickness from dehydration?

Yes, dehydration can both mimic and worsen the symptoms of altitude sickness, which is why proper hydration is critically important when at high altitudes.

Is it harder to digest food at high altitudes?

Yes, the reduced oxygen levels at high altitude can decrease blood flow to the gut, slowing down your digestive process. This is why smaller, more frequent, and easily digestible meals are recommended.

What's better at altitude, simple or complex carbs?

Complex carbohydrates like oats or quinoa are ideal for sustained energy at high altitudes, while simple carbohydrates from dried fruit or gels can provide a quick boost during exertion.

Should I increase my calorie intake at high altitude?

Yes, your metabolism increases at altitude, so consuming more calories is necessary to prevent weight loss, maintain energy, and support your body's acclimatisation efforts.

Why should I avoid alcohol at high altitude?

Alcohol acts as a diuretic and dehydrates the body, which can exacerbate altitude sickness symptoms and impair your body's adjustment to the low-oxygen environment.

Are electrolyte supplements necessary for acclimatisation?

While not strictly necessary for everyone, electrolyte mixes are highly recommended, especially during strenuous activity, to replace minerals lost through increased respiration and urination.

How can I combat a suppressed appetite at altitude?

To manage a suppressed appetite, focus on nutrient-dense, easy-to-digest foods like soups, oatmeal with dried fruit, and nuts. Small, frequent meals are often more palatable.