Everything you need to know about the ketogenic diet. Learn the science, the foods, and what to expect when your body enters ketosis. — By Tee, Certified Fitness Trainer
Keto Diet 101: What to Eat, What to Avoid, and What to Expect
By Tee | 20 January 2026 | Category: Keto Meals
The ketogenic diet has taken Australia by storm, with many people reporting increased energy, mental clarity, and significant weight loss. But what exactly is keto, and is it right for you?
What is the Ketogenic Diet?
The keto diet is a very low-carb, high-fat eating approach that shifts your body's primary fuel source from glucose (carbs) to ketones (produced from fat). This metabolic state is called "ketosis."
Keto Macros Breakdown
Fat: 70-80% of daily calories
Protein: 15-25% of daily calories
Carbohydrates: 5-10% (usually under 20-50g net carbs)
Foods to Eat on Keto
Meat, fish, and poultry
Eggs and full-fat dairy
Avocados and healthy oils (olive, coconut)
Low-carb vegetables (leafy greens, broccoli, zucchini)
Nuts and seeds
Foods to Avoid
Grains (bread, pasta, rice)
Sugar and sweetened foods
Most fruits (except berries in small amounts)
Starchy vegetables (potatoes, corn)
Legumes and beans
What to Expect
The first week can be challenging as your body adapts. Some experience the "keto flu" – temporary fatigue, headaches, and irritability. Stay hydrated, ensure adequate electrolytes, and give your body time to adjust.
Keto Made Convenient
Our keto-friendly meals are formulated to keep you in ketosis with under 10g net carbs per serve while delivering satisfying portions of quality fats and proteins.
What Ketosis Actually Is (Without the Marketing Spin)
Ketosis is a metabolic state where your liver produces ketone bodies — beta-hydroxybutyrate, acetoacetate, and acetone — from fatty acids when carbohydrate availability is restricted. These ketones become the primary fuel for your brain (which normally uses glucose), most of your heart, and large portions of your muscle tissue. Blood ketone levels above ~0.5 mmol/L are generally considered nutritional ketosis.
This is a real, measurable metabolic shift — not a wellness-industry buzzword. Endurance athletes, neurology patients (keto has been used clinically for epilepsy since the 1920s), and people with type 2 diabetes have all been studied extensively on ketogenic diets. The catch is that "keto" as commonly practised — for weight loss — works largely because protein and fat are more satiating than carbs, not because of any unique fat-burning magic. If you eat at a calorie surplus on keto, you'll still gain weight.
The Adaptation Phase (and Why People Quit)
Getting into ketosis takes 2-7 days depending on your previous diet and activity level. The transition period is where most beginners struggle. Symptoms — collectively called "keto flu" — usually include:
Fatigue, brain fog, irritability (your brain is still preferring glucose)
Headaches
Muscle cramps (especially calf cramps at night)
Constipation
Bad breath ("keto breath" — acetone exhaled through the lungs)
Most of these resolve within 1-2 weeks. The faster you get them under control, the higher your odds of sticking with the diet long enough to see results.
Electrolytes — The Single Most Important Keto Skill
When you cut carbs, your kidneys excrete a lot of water and sodium in the first week. This is the source of most "keto flu" symptoms — you're not eating a bad diet, you're just becoming mildly dehydrated and salt-depleted. Get ahead of it:
Sodium: 3-5g per day (much more than mainstream "low-salt" advice). Add salt liberally; drink a glass of warm water with a quarter-teaspoon of salt in the morning.
Potassium: 1-2g per day. Avocados, leafy greens, salmon, mushrooms, and electrolyte supplements that include K.
Magnesium: 300-400mg per day, often as supplements. Magnesium glycinate is well-absorbed and won't upset your stomach. Helps with cramps and sleep.
Foods That Will Wreck Your Ketosis Without You Noticing
"Sugar-free" products with maltitol or other sugar alcohols: Maltitol spikes blood glucose more than most people realise. Stick to erythritol, stevia, monk fruit, or allulose.
Most commercial salad dressings: Often contain added sugar or honey. Olive oil + lemon, or read the label.
"Healthy" smoothies and protein bars: Easily 30-50g carbs disguised as health food.
Hidden carbs in sauces: BBQ, teriyaki, sweet chilli, ketchup — all problematic. Move to mustard, mayo (sugar-free), hot sauce, and herb-based dressings.
Excess protein: Sounds counterintuitive, but very high protein can be partially converted to glucose via gluconeogenesis. Aim for 1.2-1.6g protein per kg lean body mass, not maximum tolerable.
Who Keto Isn't For
Keto is not appropriate for everyone. Talk to your doctor before starting if any of these apply:
You're on insulin or sulfonylureas for diabetes: Cutting carbs while on insulin can cause dangerous hypoglycaemia. Medication doses need careful adjustment.
You're pregnant or breastfeeding: Insufficient long-term safety data, and your baby's brain is developing rapidly with high glucose demand.
You have a history of disordered eating: The restriction can trigger relapse.
You have certain rare metabolic disorders (porphyria, pyruvate carboxylase deficiency, fat metabolism disorders).
You have gallbladder issues or have had your gallbladder removed: very high fat intake can cause discomfort.
How to Break Keto Safely (When the Time Comes)
Most people don't stay on strict keto forever — and that's fine. When you reintroduce carbs:
Start small (50-75g/day for a few days), don't go straight to 300g.
Prioritise whole-food carbs first: sweet potato, fruit, oats, rice — not bread, pasta, or sugar.
Expect to gain 1-3kg of water weight in the first few days. This is glycogen rebinding with water, not fat regain.
Keep your protein intake the same; just shift fat down as carbs come up.
FAQs
How long until I'll see weight loss? Most people lose 2-4kg in the first 1-2 weeks, mostly water. Real fat loss is usually 0.5-1kg per week thereafter, assuming calorie deficit. Stalls at week 3-4 are common and usually resolve with electrolyte adjustment or a slight calorie audit.
Do I need to measure ketones? Not really. If you're eating <30g net carbs, getting adequate fat and protein, and noticing the typical effects (steady energy, reduced hunger), you're in ketosis. Urine strips work for the first week or two; blood meters are more accurate but only useful if you're optimising for a specific goal.
Can I drink alcohol on keto? Some — dry wine, spirits with sugar-free mixers — fit. Beer and sweet cocktails don't. Alcohol blunts fat-burning for several hours regardless of carb content, so factor that into your weight-loss expectations.
Will keto raise my cholesterol? Total cholesterol and LDL often rise on keto. HDL also rises, triglycerides usually fall significantly, and overall cardiovascular risk markers are typically neutral or improved — but get bloods done before starting and again at 3-6 months. A small minority of people are "hyper-responders" with concerning LDL increases; they may need to moderate saturated fat or reconsider the diet.
A note on this article. Foober blog articles are researched with the assistance of AI tooling for source-gathering and structural drafting, then reviewed and edited by Tee — Foober's founder and certified fitness trainer — for accuracy, tone, and relevance. Nothing on this blog constitutes medical, nutritional, dietetic, or fitness advice tailored to your individual circumstances. Foober is a meal delivery service, not a healthcare provider. For personalised guidance — especially regarding medications, medical conditions, allergies, pregnancy, or significant dietary changes — please consult a qualified healthcare professional (your GP, an Accredited Practising Dietitian, or equivalent).
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