Guam , an organized, unincorporated territory of the United States in the western Pacific Ocean has the native Chamorro Indians as largest ethnic group, accounting for 37.1% of the total population. On this tiny island, the natives frequently consumed large amounts of a particular plant called cycas circinalis, or cycad. Actually cycad, made from the false sago palm, had been eaten by the natives for centuries. Natives also knew that plant was poisonous and for that reason they developed a ritual to render it safe for eating and facing no issue once proper purification ritual is followed. Of course, their ritual was not so great science but still it did not give them deadly diseases. (After several soaking, a chicken was fed some of the wash water. If it lived, the seed was deemed safe to eat.).
But during war times of WWII, during American invasion, the native people had suffered terrible hardships and famine. During this time, they felt scarcity of water and chicken, and started skipping cycad purification steps to avoid water wastage. Esp., the last poison testing step was completely missing. During same time, the US military doctors were astounded to find that large numbers of the Chamorro Indians, living on the Mariana Islands, were dying of a mysterious disease  that left the Indians too weak to stand or even swallow their food.
Reason behind motor neuron (A neuron conducting impulses outwards from the brain or spinal cord) disease was L-BMAA  a liver toxin that remained with cycad plant due to compromised purification ritual.
What’s the point of this narration?
Steps prescribed by ancestors based on their anubhava-siddha, nature-blessed, intuition based knowledge – it is essential to follow them as is to bear similar beneficial fruits. If we use ancestors way of living, it is advisable, not to make mindless alterations or situation led compromises.
Imagine mental toxin that remains with you, ever after you perform Yoga-Asana, due to skipping Yama and Niyama! Terrible subconscious stress! Though you feel physical freshness, deep down, there is no cleansing of soul happening! Every morning, back to the square one.
Yama (non-violence, non-illusion, non-covetousness, abstinence, non-possessiveness) and Niyama (cleanliness, satisfaction, austerity, study of the Vedic scriptures to know about God and the soul, surrender to (or worship of) God) are important. Learn to act upon them before you mimic Baba’s gymnastic/aerobics steps every morning.