Dr. Yael Adler: These Sugar Alternatives Promote Health

Coffee's negative image is outdated. It's not only harmless but genuinely health-promoting — it can help protect against liver cancer and uterine cancer, and may help prevent type 2 diabetes, Parkinson's disease, and depression. Studies have found that the optimal amount is three to five cups a day. Coffee is rich in antioxidants and contains over a thousand bioactive substances, including polyphenols, which have antioxidant and anti-inflammatory effects.

This protects cells and blood vessels and acts on the central nervous system. Coffee also stimulates digestion and has prebiotic effects, since it contains dietary fiber. That said, it's worth figuring out which type of coffee suits you best. Anyone who can't tolerate filter coffee due to its acidity should try machine-made coffee instead.

Which foods do you avoid, and why?

Sugar. I only treat myself to a slice of cheesecake on very rare occasions. I avoid highly processed foods with lots of additives and trans fats, and I barely drink alcohol. I prefer natural, whole foods and love colorful, vegetable-rich meals. I'll admit that I live so consciously because I'm a bit of a hypochondriac.

I want to outsmart fate. Ten to 30 percent of what makes a healthy life is genetic — the rest is in your own hands. I can feel that actively supporting my health does me good. It's an act of mindfulness.

Intelligent Sugar and Sweeteners: What Is Really Healthier?

The term "intelligent sugar" comes up a lot — what does it actually mean?

Tagatose, galactose, mannose, allulose, ribose, trehalose, and isomaltulose are all referred to as "intelligent sugars." These have demonstrated health benefits and can also be used as sweeteners — in cheesecake, for example.

Unlike conventional table sugar, they tend to influence metabolism in beneficial ways — for instance by preventing blood sugar spikes, improving gut flora, supporting fat metabolism, and even enhancing memory performance. This applies in particular to tagatose, galactose, and mannose.

Galactose occurs naturally in breast milk and can be obtained through the enzymatic splitting of lactose; tagatose can also be produced through fermentation from corn starch — it improves long-term blood sugar levels and strengthens both the gut microbiome and dental health.

Galactose helps build brain cells, enhances communication between them, and — crucially — supplies energy to cells affected by dementia, which often exhibit insulin resistance, because galactose can be metabolized independently of insulin.

Mucous membranes also benefit: more mucus is produced, which is advantageous for protecting the gut and respiratory tract. There is also research suggesting that these types of sugar could play a supportive role in cancer therapy. Allulose — a rare sugar — also shows promising effects. It may have anti-inflammatory properties, positively affect brain function, and protect the liver.

What do you think of artificial sweeteners?

Sugar substitutes and artificial sweeteners cannot be recommended as a healthier alternative. There are various theories and studies on the subject, but one important point is that they appear to negatively affect gut flora. This can lead to a deterioration in glucose tolerance, which may in turn promote diabetes and insulin resistance.

What does a gut-friendly diet look like?

Our gut health plays a crucial role, because through the gut-brain axis, the gut is directly connected to our cognitive performance and our mood. A healthy microbiome improves digestion, strengthens the immune system, and has a positive effect on the sleep-wake cycle.

A microbiome-friendly diet is built around plant foods. You should aim for 30 different plants per week — as recommended by the American Gut Project — and these include vegetables, fruit, nuts, seeds, kernels, legumes, spices, herbs, and fermented foods, which are especially beneficial because they are also probiotic.

You should also aim for 30 grams of dietary fiber per day. Soluble fiber in particular nourishes the beneficial bacteria.

Diet for Healthy Skin: Foods Recommended by Yael Adler

Which foods help keep skin looking young?

Colorful plants, above all — for example, the plant pigment beta-carotene from carrot juice, lycopene from tomato paste, chlorophyll from green leafy vegetables, or matcha tea. Nuts are another superfood, especially walnuts. They contain vitamin E, B vitamins, and anti-inflammatory omega-3 fatty acids. Alongside nuts, you should also eat plenty of seeds: flaxseeds, hemp seed husks, wheat germ, and psyllium husks.

It's definitely worth having a blood test done from time to time to see what your body is actually lacking. Many people have too little vitamin D with K2. Zinc is often low, as are selenium and omega-3 fatty acids.

And many women have iron levels that are too low. My tip: please make sure to use iodized salt. A lot of people think Himalayan salt is a better choice, but then they miss out on the iodine their thyroid needs. And a healthy thyroid means healthy skin.

What should you look for when buying supplements?

Quality is key, and this can be recognized by DIN standards and other quality seals. Additives such as titanium dioxide, artificial colorings, sweeteners, or unnecessary fillers should not be present — and of course no sugar. Ideally, the products come from the EU, as they then also comply with EU requirements.

You recommend eating a tablespoon of tomato paste every day — why?

Yes, with a drop of olive oil — either on its own, spread on bread, or stirred into soup. It provides a good dose of lycopene, a powerful antioxidant and carotenoid that counteracts UV damage in the skin and cellular aging, has cancer-inhibiting properties, and is particularly concentrated and bioavailable in tomato paste.

Which spices do you use regularly?

Spices and herbs should be enjoyed in a colorful mix — whatever you like. Turmeric (with pepper), for example, has anti-inflammatory effects. Ginger is antioxidant and good for digestion. Garlic has antibacterial properties and dilates blood vessels, thereby lowering blood pressure — as does cinnamon. Cumin and oregano are antimicrobial.

Chili can inhibit inflammation and promotes fat burning. Cloves have digestive, antimicrobial, antioxidant, antiviral, and even local anesthetic effects — the latter being well known in dentistry. Cumin is used in Ayurvedic medicine to support liver and kidney function. Parsley helps build collagen, has a diuretic effect, reduces blood lipids, and provides vitamin C. I could go on with many more examples…

Alcohol, Metabolism, and Weight Loss: What Really Matters

How much alcohol is actually acceptable?

The official recommendation is no more than 10 to 12 grams of alcohol per day for women — double that for men — which works out to a small glass of wine for women (125 ml) and a larger one for men (double the amount).

For a time, people thought drinking alcohol five days a week was fine, with two alcohol-free days afterward. But that view is now considered outdated as well. The current thinking is that every drop of alcohol is one too many, because alcohol is converted into acetaldehyde, a cellular toxin.

This can increase the cancer risk and cause the skin — and the body as a whole — to age more quickly. One small exception is said to apply to red wine, which does contain some quite beneficial plant compounds, and small sips in moderate amounts, such as with a meal, are considered acceptable.

If a very health-conscious person occasionally drinks a little alcohol, significant negative effects are probably unlikely. In the Blue Zones, where the world's longest-lived people reside, that is at least how it tends to be handled. A sociable gathering with a little alcohol reduces stress.

Can you give us six quick tips for boosting calorie consumption?

1. More movement in everyday life — for example, taking the stairs instead of the elevator.
2. Strength training, so we build muscle as calorie-burning engines.
3. High-intensity interval training.
4. Ice bathing or cold showers. This stimulates thermogenesis, in part by increasing energy-burning brown adipose tissue.
5. A consistent sleep rhythm and sufficiently long sleep (7–8 hours). Sleep deprivation actually lowers basal metabolic rate. Ideally, we should go to sleep before midnight and avoid eating too many carbohydrates in the evening — this supports better fat breakdown and muscle building. One tip: if you suffer from sleep apnea, you should definitely have it treated, as it places enormous stress on the body, makes weight loss virtually impossible, and is even life-shortening.
6. Additional weight-loss aids include a more generous protein intake of 1.3–1.6 grams per kilogram of body weight — preferably from plant sources — complex carbohydrates instead of free sugars, and avoiding highly processed industrial foods with high caloric density. The beneficial bacteria associated with weight loss and a healthy metabolism thrive on at least 30 grams of dietary fiber per day. Healthy oils such as extra virgin olive oil, nuts, and avocado are also beneficial: they keep you feeling full for longer, reduce cravings, act as flavor carriers, and aid in the absorption of fat-soluble vitamins.